Test Suite and Sample Inputs¶
PSI4 is distributed with an extensive test suite, which can
be found in psi4/tests. After building the source code, these
can automatically be run by running ctest
in the compilation
directory. More info on ctest
options can be found
here. Sample input files
can be found in the psi4/samples subdirectory of the top-level Psi
directory. The samples and a brief description are provided below.
Sample inputs accessible through interfaced executables are bulleted below.
Sample inputs for PSI4 as distributed are below.
Input File |
Description |
---|---|
Matches Table II a-CCSD(T)/cc-pVDZ H2O @ 2.5 * Re value from Crawford and Stanton, IJQC 98, 601-611 (1998). |
|
SCF/sto-3g optimization with a hessian every step |
|
optimization with method defined via cbs |
|
RHF-CC2-LR/STO-3G optical rotation of (S)-methyloxirane. gauge = length, omega = (589 355 nm) |
|
CC3/cc-pVDZ H2O \(R_e\) geom from Olsen et al., JCP 104, 8007 (1996) |
|
Sample HF/cc-pVDZ H2O computation all derivatives |
|
SAPT0(ROHF) open-shell computation of CN - Ne interaction energy First with jun-cc-pVDZ and density fitted integrals with ROHF Then with cc-pVDZ and direct integrals, except for dispersion that is computed with cc-pVDZ-ri density fitting with ROHF. |
|
integral conventional unrestricted REMP/cc-pVDZ energies for the H2O+ molecule. results were independently verified against the initial wavels implementation |
|
OMP3 cc-pVDZ gradient for the NO radical |
|
Restricted DF-DCT ODC-12 gradient for ethylene with cc-pVDZ/cc-pVDZ-RI standard/auxiliary basis set |
|
EOM-CC3(UHF) on CH radical with user-specified basis and properties for particular root |
|
This checks that all energy methods can run with a minimal input and set symmetry. |
|
HF and DFT variants single-points on zmat methane, mostly to test that PSI variables are set and computed correctly. Now also testing that CSX harvesting PSI variables correctly update ref_dft_2e/xc due to new BraggSlater radii |
|
CCSD/sto-3g optical rotation calculation (both gauges) at two frequencies on methyloxirane |
|
DF SCF 6-31G analytical vs finite-difference tests Tests DF UHF hessian code for Ca != Cb |
|
OMP2 cc-pVDZ energy for the NO molecule. |
|
check distributed driver is correctly passing function kwargs |
|
CC3(UHF)/cc-pVDZ H2O \(R_e\) geom from Olsen et al., JCP 104, 8007 (1996) |
|
OLCCD cc-pVDZ energy with B3LYP initial guess for the NO radical |
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Various gradients for a strained helium dimer and water molecule |
|
DF-MP2 cc-pVDZ gradients for the H2O molecule. |
|
Test FNO-DF-CCSD(T) energy |
|
CCSD/sto-3g optical rotation calculation (length gauge only) at two frequencies on methyloxirane |
|
Tests the Psi4 SF-SAPT code |
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Test computing values of basis functions (puream and non-puream) at points |
|
DCT calculation for the triplet O2 using ODC-06 and ODC-12 functionals. Only simultaneous algorithm is tested. |
|
OMP2 cc-pVDZ energy for the NO molecule. |
|
Analytic SVWN frequencies, compared to finite difference values |
|
ROHF-EOM-CCSD/DZ analytic gradient lowest \(^{2}B_1\) state of H2O+ (A1 excitation) |
|
Sample UHF/cc-pVDZ H2O computation on a doublet cation, using RHF/cc-pVDZ orbitals for the closed-shell neutral as a guess |
|
DFT Functional Smoke Test |
|
cc3: RHF-CCSD/6-31G** H2O geometry optimization and vibrational frequency analysis by finite-differences of gradients |
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Various gradients for a strained helium dimer and water molecule |
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Mk-MRCCSD single point. \(^3 \Sigma ^-\) O2 state described using the Ms = 0 component of the triplet. Uses ROHF triplet orbitals. |
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6-31G** H2O Test CISD Energy Point |
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Carbon/UHF Fractionally-Occupied SCF Test Case |
|
6-31G** H2O+ Test CISD Energy Point |
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checks that all SAPT physical components (elst, exch, indc, disp) and total IE are being computed correctly for SAPT2+3(CCD)dMP2/aug-cc-pvdz and all lesser methods thereof. |
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SCF DZ finite difference frequencies by gradients for C4NH4 |
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DF-BP86-D2 cc-pVDZ frozen core gradient of S22 HCN update ref gradient due to new BraggSlater radii |
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Test SAD SCF guesses on noble gas atom |
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UHF-CCSD(T)/cc-pVDZ \(^{3}B_1\) CH2 geometry optimization via analytic gradients |
|
6-31G** H2O+ Test CISD Energy Point |
|
DF-CCSD(T) cc-pVDZ gradient for the NH molecule. |
|
A test of the basis specification. Various basis sets are specified outright and in blocks, both orbital and auxiliary. Constructs libmints BasisSet objects through the constructor that calls qcdb.BasisSet infrastructure. Checks that the resulting bases are of the right size and checks that symmetry of the Molecule observes the basis assignment to atoms. |
|
check that methods can act on single atom |
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comparison of DF-MP2 and DLPNO-MP2 with a cartesian basis set |
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DF-BP86-D2 cc-pVDZ frozen core gradient of S22 HCN updated ref gradient due to new BraggSlater radii |
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Tests all grid pruning options available and screening of small weights. Check against grid size. |
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reproduces dipole moments in J.F. Stanton’s “biorthogonal” JCP paper |
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DF-CCSD(T) cc-pVDZ energy for the H2O molecule. |
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Tests RHF CCSD(T)gradients |
|
density fitted REMP/cc-pVDZ energies for the CH3 radical |
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MP(n)/aug-cc-pVDZ BH Energy Point, with n=2-19. Compare against M. L. Leininger et al., J. Chem. Phys. 112, 9213 (2000) |
|
td-camb3lyp with DiskDF and method/basis specification |
|
OMP2.5 cc-pVDZ energy for the H2O molecule. |
|
SCF with various combinations of pk/density-fitting, castup/no-castup, and spherical/cartesian settings. Demonstrates that puream setting is getting set by orbital basis for all df/castup parts of calc. Demonstrates that answer doesn’t depend on presence/absence of castup. Demonstrates (by comparison to castup3) that output file doesn’t depend on options (scf_type) being set global or local. This input uses global. |
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6-31G H2O Test for coverage |
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SCF cc-pVDZ geometry optimzation, with Z-matrix input |
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RHF-CCSD 6-31G** all-electron optimization of the H2O molecule |
|
test FCIDUMP functionality for rhf/uhf |
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Extrapolated water energies - density-fitted version |
|
CC2(RHF)/cc-pVDZ energy of H2O. |
|
Density fitted MP2 cc-PVDZ/cc-pVDZ-RI computation of formic acid dimer binding energy using explicit specification of ghost atoms. This is equivalent to the dfmp2_1 sample but uses both (equivalent) specifications of ghost atoms in a manual counterpoise correction. |
|
SCF 6-31G(d) optimization of TS for HCN to HNC Performs finite difference hessian calculation. Then optimizes using previous orbitals for scf guess, in subsequent calculations. The last two displacements of the hessian break the plane of symemtry, This test confirms that only the reference geometry, with the correct symmetry, writes orbitals to disk. SCF will fail (ValidationError) otherwise. |
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Test of the superposition of atomic densities (SAD) guess, using a highly distorted water geometry with a cc-pVDZ basis set. This is just a test of the code and the user need only specify guess=sad to the SCF module’s (or global) options in order to use a SAD guess. The test is first performed in C2v symmetry, and then in C1. |
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OMP2 cc-pVDZ energy for the H2O molecule. |
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Mk-MRCCSD(T) single point. \(^1A_1\) CH2 state described using the Ms = 0 component of the singlet. Uses RHF singlet orbitals. |
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Various basis set extrapolation tests |
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SAPT2+(3) aug-cc-pVDZ computation of the formamide dimer interaction energy, using the aug-cc-pVDZ-JKFIT DF basis for SCF and aug-cc-pVDZ-RI for SAPT. This example uses frozen core as well as MP2 natural orbital approximations. |
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This test case shows an example of running the I-SAPT0/jun-cc-pVDZ computation for 2,4-pentanediol (targeting the intramolecular hydrogen bond between the two hydroxyl groups) The SIAO1 link partitioning algorithm is used. |
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Second-order SCF convergnece: Benzene |
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ROHF-CCSD/cc-pVDZ \(^{3}B_1\) CH2 geometry optimization via analytic gradients |
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DF-OMP3 cc-pVDZ energy for the H2O molecule. |
|
Tests to determine full point group symmetry. Currently, these only matter for the rotational symmetry number in thermodynamic computations. |
|
LCCD cc-pVDZ gradient for the NO radical |
|
updated dldf reference to new BraggSlater radii Dispersionless density functional (dlDF+D) internal match to Psi4 Extensive testing has been done to match supplemental info of Szalewicz et. al., Phys. Rev. Lett., 103, 263201 (2009) and Szalewicz et. al., J. Phys. Chem. Lett., 1, 550-555 (2010) |
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Test method/basis with disk_df |
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External potential calculation involving a TIP3P water and a QM water. Gradient on the external charges is compared to gradient on the QM atoms to validate the gradient on the charges. |
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DFT Functional Test |
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Single point gradient of 1-2B2 state of H2O+ with EOM-CCSD |
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DF-CCDL cc-pVDZ energy for the H2O molecule. |
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MP2.5 cc-pVDZ gradient for the NO radical |
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DF-CCSD cc-pVDZ gradients for the H2O molecule. |
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force occupations in scf |
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SCF cc-pVTZ geometry optimzation, with Z-matrix input |
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routing check on lccd, lccsd, cepa(0). |
|
DF-MP2 frequency by difference of energies for H2O |
|
Tests SCF gradient in the presence of a dipole field |
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Mk-MRCCSD(T) single point. \(^1A_1\) O$_3` state described using the Ms = 0 component of the singlet. Uses TCSCF orbitals. |
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Cholesky decomposed REMP/cc-pVDZ energies for the CH3 radical |
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Density fitted MP2 cc-PVDZ/cc-pVDZ-RI computation of formic acid dimer binding energy using automatic counterpoise correction. Monomers are specified using Cartesian coordinates. |
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SCF DZ allene geometry optimzation, with Cartesian input |
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incremental Cholesky filtered SCF |
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Test LDA stability analysis against QChem. |
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6-31G H2O Test FCI Energy Point |
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many-body different levels of theory on each body of helium tetramer |
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RHF interaction energies using nbody and cbs parts of the driver Ne dimer with mp2/v[dt]z + d:ccsd(t)/vdz |
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DF-SCF cc-pVDZ of benzene-hydronium ion, scanning the dissociation coordinate with Python’s built-in loop mechanism. The geometry is specified by a Z-matrix with dummy atoms, fixed parameters, updated parameters, and separate charge/multiplicity specifiers for each monomer. One-electron properties computed for dimer and one monomer. |
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Test initial SCF guesses on FH and FH+ in cc-pVTZ basis |
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SAPT2+3 with S^inf exch-ind30 Geometries taken from the S66x10 database, the shortest-range point (R = 0.7 R_e) |
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MP2 cc-pVDZ gradient for the H2O molecule. |
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cc-pvdz H2O Test CEPA(1) Energy |
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Extrapolated water energies - conventional integrals version |
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Tests OMP2 gradient in the presence of a dipole field |
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Advanced python example sets different sets of scf/post-scf conv crit and check to be sure computation has actually converged to the expected accuracy. |
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DC-06 calculation for the He dimer. This performs a simultaneous update of the orbitals and cumulant, using DIIS extrapolation. Four-virtual integrals are handled in the AO Basis, using integrals stored on disk. |
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CASSCF/6-31G** energy point |
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DSD-PBEP86 S22 Ammonia test |
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SAPT(DFT) aug-cc-pVDZ interaction energy between Ne and Ar atoms. |
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RHF-CC2-LR/cc-pVDZ dynamic polarizabilities of HOF molecule. |
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This test case shows an example of running the I-SAPT0/aug-cc-pVDZ computation for a positively charged system, illustrating the cation-pi interaction. The SIAO1 link partitioning algorithm is used. The system is taken from http://dx.doi.org/10.1016/j.comptc.2014.02.008 |
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RHF-CCSD(T) cc-pVQZ frozen-core energy of the BH molecule, with Cartesian input. This version tests the FROZEN_DOCC option explicitly |
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Test of the superposition of atomic densities (SAD) guess, using a highly distorted water geometry with a cc-pVDZ basis set. This is just a test of the code and the user need only specify guess=sad to the SCF module’s (or global) options in order to use a SAD guess. The test is first performed in C2v symmetry, and then in C1. |
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Mk-MRCCSD(T) single point. \(^1A_1\) CH2 state described using the Ms = 0 component of the singlet. Uses RHF singlet orbitals. |
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Test omega is setable updated wb97x_20,wb97x_03 to account for new BraggSlater radii |
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RHF-CC2-LR/cc-pVDZ optical rotation of H2O2. gauge = both, omega = (589 355 nm) |
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Test Gibbs free energies at 298 K of N2, H2O, and CH4. |
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Cholesky filter a complete basis |
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OMP2 cc-pVDZ energy for the NO molecule. |
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DCT calculation for the NH3+ radical using the ODC-12 and ODC-13 functionals. This performs both simultaneous and QC update of the orbitals and cumulant using DIIS extrapolation. Four-virtual integrals are first handled in the MO Basis for the first two energy computations. In the next computation ao_basis=disk algorithm is used, where the transformation of integrals for four-virtual case is avoided. |
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CI/MCSCF cc-pvDZ properties for Potassium nitrate (rocket fuel!) |
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DF-CCSD(T) cc-pVDZ energy for the NH molecule. |
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CASSCF/6-31G** energy point |
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A general test of the MintsHelper function |
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CASSCF/6-31G** energy point. Check energy with frozen core/virtual orbs. after semicanonicalization. |
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MBIS calculation on H2O |
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Optimize H2O HF/cc-pVDZ |
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MBIS calculation on OH- (Expanded Arrays) |
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DF-CCSD cc-pVDZ energy for the H2O molecule. |
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Single point energies of multiple excited states with EOM-CCSD |
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MP3 cc-pVDZ gradient for the NO radical |
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H2O CISD/6-31G** Optimize Geometry by Energies |
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Ne-Xe dimer MP2 energies with ECP, with electrons correlated then frozen. |
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UHF-CCSD(T) cc-pVDZ frozen-core energy for the \(^2\Sigma^+\) state of the CN radical, with Z-matrix input. |
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6-31G** H2O CCSD optimization by energies, with Z-Matrix input |
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Example of state-averaged CASSCF for the C2 molecule |
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RHF-CC2-LR/STO-3G optical rotation of (S)-methyloxirane. gauge = both, omega = (589 355 nm) |
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ROHF-EOM-CCSD/DZ on the lowest two states of each irrep in \(^{3}B_1\) CH2. |
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OMP2 cc-pVDZ energy for the H2O molecule. |
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UHF STO-3G (Cartesian) and cc-pVDZ (spherical) water Hessian test, against Psi3 reference values. This test should match RHF values exactly |
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DF-CCSD(T) cc-pVDZ gradients for the H2O molecule. |
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SAPT(DFT) aug-cc-pVDZ computation for the water dimer interaction energy. |
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SCF DZ allene geometry optimization, with Cartesian input, first in c2v symmetry, then in Cs symmetry from a starting point with a non-linear central bond angle. |
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SAPT0 cc-pVDZ computation of the ethene-ethyne interaction energy, using the cc-pVDZ-JKFIT RI basis for SCF and cc-pVDZ-RI for SAPT. Monomer geometries are specified using Cartesian coordinates. |
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Spin-restricted DC-06 counterpart of dct1. |
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Compute the dipole polarizability for water with custom basis set. |
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DF-CCD cc-pVDZ energy for the H2O molecule. |
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SCF cc-pVDZ geometry optimzation of ketene, starting from bent structure |
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Test of SFX2C-1e on Water uncontracted cc-pVDZ The reference numbers are from Lan Cheng’s implementation in Cfour |
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integral conventional OO-REMP/cc-pVDZ engrad single points for the H2O molecule. |
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Benzene Dimer DF-HF/cc-pVDZ |
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Tests analytic CC2 gradients |
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Kr–Kr nocp energies with all-electron basis set to check frozen core |
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SCF STO-3G finite-difference frequencies from energies for H2O |
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test roundtrip-ness of dict repr for psi4.core.Molecule and qcdb.Molecule |
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RHF aug-cc-pVQZ energy for the BH molecule, with Cartesian input. Various gradients for a strained helium dimer and water molecule |
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Compute the IRC for HCN <-> NCH interconversion at the RHF/DZP level of theory. |
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ROHF-CCSD cc-pVDZ frozen-core energy for the \(^2\Sigma^+\) state of the CN radical, with Cartesian input. |
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Water-Argon complex with ECP present; check of RHF Hessian |
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Lithium test for coverage |
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Compute the IRC for HOOH torsional rotation at the RHF/DZP level of theory. |
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meta-GGA gradients of water and ssh molecules reference gradients updated due to new BraggSlater radii |
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DFT JK on-disk test |
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This test case shows an example of running and analyzing a standard F-SAPT0/jun-cc-pvdz procedure for HSG-18-dimer from the HSG database. |
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Test if the the guess read in the same basis converges. |
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EOM-CCSD/6-31g excited state transition data for water with two excited states per irrep |
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EOM-CCSD/6-31g excited state transition data for water cation |
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RKS Density Matrix based-Integral Screening Test for benzene |
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density fitted OO-REMP/cc-pVDZ engrad single points for the H2O+ molecule. |
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td-camb3lyp with DiskDF and method/basis specification |
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Mk-MRCCSD frequencies. \(^1A_1\) O$_3` state described using the Ms = 0 component of the singlet. Uses TCSCF orbitals. |
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Test FNO-QCISD(T) computation |
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EOM-CC2/cc-pVDZ on H2O2 with two excited states in each irrep |
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Test of all different algorithms and reference types for SCF, on singlet and triplet O2, using the cc-pVTZ basis set. |
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RHF-CC2-LR/cc-pVDZ optical rotation of H2O2. gauge = length, omega= (589 355 nm) |
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DFT Functional Test for Range-Seperated Hybrids and Ghost atoms |
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Convergence of many-body gradients of different BSSE schemes |
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Test of the superposition of atomic densities (SAD) guess, using a highly distorted water geometry with a cc-pVDZ basis set. This is just a test of the code and the user need only specify guess=sad to the SCF module’s (or global) options in order to use a SAD guess. The test is first performed in C2v symmetry, and then in C1. |
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Patch of a glycine with a methyl group, to make alanine, then DF-SCF energy calculation with the cc-pVDZ basis set |
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Compute three IP and 2 EA’s for the PH3 molecule |
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He Dimer VV10 functional test. notes: DFT_VV10_B/C overwrites the NL_DISPERSION_PARAMETERS tuple updated ‘bench’ reference values for new BraggSlater radii. |
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Accesses basis sets, databases, plugins, and executables in non-install locations |
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H2 with tiny basis set, to test basis set parser’s handling of integers |
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Superficial test of PubChem interface |
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Computation of NoCP-corrected water trimer gradient (geometry from J. Chem. Theory Comput. 11, 2126-2136 (2015)) |
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apply linear fragmentation algorithm to a water cluster |
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Scan fractional occupation of electrons updated values due to new BraggSlater radii |
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Test G2 method for H2O |
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An example of using BLAS and LAPACK calls directly from the Psi input file, demonstrating |
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Compute the dipole, quadrupole, and traceless quadrupoles for water. |
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SCF level shift on an RKS computation |
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RHF cc-pVQZ energy for the BH molecule, with Cartesian input. |
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CCSD/cc-pVDZ dipole polarizability at two frequencies |
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6-31G H2O Test FCI Energy Point |
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Maximum Overlap Method (MOM) Test. MOM is designed to stabilize SCF convergence and to target excited Slater determinants directly. |
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Cholesky decomposed OO-REMP/cc-pVDZ energy for the H2O molecule. |
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DFT integral algorithms test, performing w-B97 RKS and UKS computations on water and its cation, using all of the different integral algorithms. This tests both the ERI and ERF integrals. |
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OLCCD cc-pVDZ gradient for the H2O molecule. |
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check nonphysical masses possible |
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RHF STO-3G dipole moment computation, performed by applying a finite electric field and numerical differentiation. |
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OLCCD cc-pVDZ gradient for the NO radical |
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EOM-CCSD/cc-pVDZ on H2O2 with two excited states in each irrep |
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Numpy interface testing |
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RHF-B-CCD(T)/6-31G** H2O single-point energy (fzc, MO-basis \(\langle ab|cd \rangle\)) |
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OLCCD cc-pVDZ freqs for C2H2 |
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Ne atom RASCI/cc-pVQZ Example of split-virtual CISD[TQ] from Sherrill and Schaefer, J. Phys. Chem. XXX This uses a “primary” virtual space 3s3p (RAS 2), a “secondary” virtual space 3d4s4p4d4f (RAS 3), and a “tertiary” virtual space consisting of the remaining virtuals. First, an initial CISD computation is run to get the natural orbitals; this allows a meaningful partitioning of the virtual orbitals into groups of different importance. Next, the RASCI is run. The split-virtual CISD[TQ] takes all singles and doubles, and all triples and quadruples with no more than 2 electrons in the secondary virtual subspace (RAS 3). If any electrons are present in the tertiary virtual subspace (RAS 4), then that excitation is only allowed if it is a single or double. |
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Tests DF-MP2 gradient in the presence of a dipole field |
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SAPT2+3(CCD) aug-cc-pVDZ+midbond computation of the water dimer interaction energy, using the aug-cc-pVDZ-JKFIT DF basis for SCF and aug-cc-pVDZ-RI for SAPT. |
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ROHF and UHF-B-CCD(T)/cc-pVDZ \(^{3}B_1\) CH2 single-point energy (fzc, MO-basis \(\langle ab|cd \rangle\) ) |
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Test parsed and exotic calls to energy() like zapt4, mp2.5, and cisd are working |
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Example potential energy surface scan and CP-correction for Ne2 |
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OMP2 cc-pVDZ energy for the NO molecule. |
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DF-CCSD(AT) cc-pVDZ energy for the H2O molecule. |
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MP2/aug-cc-pvDZ many body energies of an arbitrary Helium complex, addressing 4-body formulas |
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Compute three IP and 2 EA’s for the PH3 molecule |
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DF-OMP2.5 cc-pVDZ energy for the H2O molecule. |
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RHF-EOM-CC2/cc-pVDZ lowest two states of each symmetry of H2O. |
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td-wb97x excitation energies of singlet states of h2o, wfn passing |
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Frozen-core CCSD(ROHF)/cc-pVDZ on CN radical with disk-based AO algorithm |
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Extrapolated water energies |
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Check that C++ Molecule class and qcdb molecule class are reading molecule input strings identically |
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Double-hybrid density functional B2PYLP. Reproduces portion of Table I in S. Grimme’s J. Chem. Phys 124 034108 (2006) paper defining the functional. |
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DFT (LDA/GGA) test of custom implementations in: gga_superfuncs.py |
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OMP2 cc-pVDZ energy for the H2O molecule. |
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SCF/cc-pVDZ optimization example with frozen cartesian |
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RHF CCSD(T) cc-pVDZ frozen-core energy of C4NH4 Anion |
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Tests SAPT0-D corrections, with a variety of damping functions/parameters |
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DF-MP2 frequency by difference of energies for H2O |
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SCS-OMP2 cc-pVDZ geometry optimization for the H2O molecule. |
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sapt0 of charged system in ECP basis set |
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SAPT0 with S^inf exch-disp20 |
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sapt example with orbital freezing with alkali metal and dMP2 |
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Spectroscopic constants of H2, and the full ci cc-pVTZ level of theory |
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CCSD Response for H2O2 |
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CC2(UHF)/cc-pVDZ energy of H2O+. |
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LibXC density screening test. Tests empty, C-only, X-only and XC superfunctionals. ‘super_mix’ showcases how to use different screening values for X and C parts. SCF will fail or crash (nans) without screening! |
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This is a shorter version if isapt1 - does not do cube plots. See isapt1 for full details |
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Density fitted MP2 energy of H2, using density fitted reference and automatic looping over cc-pVDZ and cc-pVTZ basis sets. Results are tabulated using the built in table functions by using the default options and by specifiying the format. |
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SCF STO-3G geometry optimzation, with Z-matrix input |
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B3LYP cc-pVDZ geometry optimzation of phenylacetylene, starting from not quite linear structure updated reference due to new BraggSlater radii |
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Extrapolated energies with delta correction |
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This checks that all energy methods can run with a minimal input and set symmetry. |
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EDIIS test case from 10.1063/1.1470195 |
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DF-CCSD cc-pVDZ gradients for the H2O molecule. |
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conventional and density-fitting mp2 test of mp2 itself and setting scs-mp2 |
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ZAPT(n)/6-31G NH2 Energy Point, with n=2-25 |
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Example of state-averaged CASSCF for the C2 molecule see C. D. Sherrill and P. Piecuch, J. Chem. Phys. 122, 124104 (2005) |
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UHF and ROHF Linear Exchange Algorithm test for benzyl cation |
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Extrapolated water energies |
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SCF DZ finite difference frequencies by energies for C4NH4 |
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MOM excitation from LUMO HOMO+4 |
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ROHF stability analysis check for CN with cc-pVDZ. This test corresponds to the rohf-stab test from Psi3. |
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Omega optimization for LRC functional wB97 on water |
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Intercalls among python wrappers- database, cbs, optimize, energy, etc. Though each call below functions individually, running them all in sequence or mixing up the sequence is aspirational at present. Also aspirational is using the intended types of gradients. |
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Test individual integral objects for correctness. |
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6-31G** H2O Test RASSCF Energy Point will default to only singles and doubles in the active space |
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DFT (hybrids) test of implementations in: hybrid_superfuncs.py |
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OLCCD cc-pVDZ energy with ROHF initial guess for the NO radical |
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ROHF frontier orbitals of CH2(s) and CH2(t). |
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Various DCT analytic gradients for the O2 molecule with 6-31G basis set |
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6-31G(d) optimization of SF4 starting from linear bond angle that is not linear in the optimized structure but is in a symmetry plane of the molecule. |
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comparison of DF-MP2 and DLPNO-MP2 with a CBS extrapolation |
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OMP2.5 cc-pVDZ gradient for the NO radical |
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Tests CCENERGY’s CCSD gradient in the presence of a dipole field |
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OMP3 cc-pVDZ energy for the H2O molecule |
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EOM-CC3/cc-pVTZ on H2O |
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RHF-CCSD/cc-pVDZ energy of H2O partitioned into pair energy contributions. |
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F-SAPT0/jun-cc-pvdz procedure for methane dimer |
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run some BLAS benchmarks |
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6-31G** H2O Test CISD Energy Point with subspace collapse |
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6-31G** UHF CH2 3B1 optimization. Uses a Z-Matrix with dummy atoms, just for demo and testing purposes. |
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TD-HF test variable access |
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Single point energies of multiple excited states with EOM-CCSD |
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DFT Functional Test |
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DF-MP2 cc-pVDZ gradient for the NO molecule. |
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External potential calculation with one Ghost atom and one point charge at the same position. |
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CONV SCF 6-31G analytical vs finite-difference tests Tests UHF hessian code for Ca != Cb |
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6-31G H2O Test FCI Energy Point |
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DF-OMP2.5 cc-pVDZ gradients for the H2O molecule. |
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SCF STO-3G geometry optimzation, with Z-matrix input, by finite-differences |
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6-31G** H2O+ Test CISD Energy Point |
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Mk-MRPT2 single point. \(^1A_1\) F2 state described using the Ms = 0 component of the singlet. Uses TCSCF singlet orbitals. |
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MP2 cc-pVDZ gradient for the NO radical |
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Optimization followed by frequencies H2O HF/cc-pVDZ |
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Quick test of external potential in F-SAPT (see fsapt1 for a real example) |
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RHF-CCSD-LR/cc-pVDZ static polarizability of HOF |
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Tests RHF CCSD(T)gradients |
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Vibrational and thermo analysis of several water isotopologs. Demonstrates Hessian reuse for different temperatures and pressures but not for different isotopologs. |
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Check that basis sets can be input with explicit angular momentum format |
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check that CC is returning the same values btwn CC*, FNOCC, and DFOCC modules |
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SCF level shift on a CUHF computation |
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UHF-ODC-12 and RHF-ODC-12 single-point energy for H2O. This performs a simultaneous update of orbitals and cumulants, using DIIS extrapolation. Four-virtual integrals are handled in the AO basis, where integral transformation is avoided. In the next RHF-ODC-12 computation, AO_BASIS=NONE is used, where four-virtual integrals are transformed into MO basis. |
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Vibrational and thermo analysis of several water isotopologs. Demonstrates Hessian reuse for different temperatures, pressures, and isotopologs |
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The multiple guesses for DCT amplitudes for ODC-12. |
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RKS Linear Exchange Algorithm test for benzene |
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Single point gradient of 1-2B1 state of H2O+ with EOM-CCSD |
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DF SCF 6-31G UHFl vs RHF test Tests DF UHF hessian code for Ca = Cb |
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Similar to mints2, but using the BSE to specify the basis sets |
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Water-Argon complex with ECP present; check of UHF Hessian |
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usapt example with empty beta due to frozen core |
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Computation of VMFC-corrected water trimer Hessian (geometry from J. Chem. Theory Comput. 11, 2126-2136 (2015)) |
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This checks that all energy methods can run with a minimal input and set symmetry. |
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Triple and Singlet Oxygen energy SOSCF, also tests non-symmetric density matrices |
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Fractional occupation with symmetry |
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OMP3 cc-pCVDZ energy with ROHF initial guess for the NO radical |
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Test of SFX2C-1e on Water cc-pVDZ-DK. In this test the Dirac equation is solved in the uncontracted cc-pVDZ-DK basis. The reference numbers are from Lan Cheng’s implementation in Cfour |
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SCF level shift on a UHF computation |
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MBIS calculation on OH radical |
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CASSCF/6-31G** energy point |
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OMP2.5 cc-pVDZ gradient for the H2O molecule. |
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Benzene vertical singlet-triplet energy difference computation, using the PubChem database to obtain the initial geometry, which is optimized at the HF/STO-3G level, before computing single point energies at the RHF, UHF and ROHF levels of theory. |
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Analytic UKS SVWN frequencies, compared to finite difference values |
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SAPT(DFT) aug-cc-pVDZ interaction energy between Ne and Ar atoms. |
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OMP2.5 cc-pVDZ energy for the H2O molecule. |
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Multilevel computation of water trimer energy (geometry from J. Chem. Theory Comput. 11, 2126-2136 (2015)) |
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A range-seperated gradient for SO2 to test disk algorithms by explicitly setting low memory |
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Single point gradient of 1-1B2 state of H2O with EOM-CCSD |
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density fitted OO-REMP/cc-pVDZ engrad single points for the H2O+ molecule. |
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6-31G** H2O Test RASSCF Energy Point will default to only singles and doubles in the active space |
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Restricted DF-DCT ODC-12 energies with linearly dependent basis functions |
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MOM excitation from LUMO HOMO+3 |
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Mk-MRCCSD(T) single point. \(^1A_1\) CH2 state described using the Ms = 0 component of the singlet. Uses RHF singlet orbitals. |
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MP2/aug-cc-pv[DT]Z many body energies of an arbitrary Helium complex Size vs cost tradeoff is rough here |
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F-SAPT0/jun-cc-pvdz procedure for methane dimer |
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density fitted OO-REMP/cc-pVDZ engrad single points for the H2O molecule. |
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MP2 cc-pvDZ properties for Nitrogen oxide |
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integral conventional OO-REMP/cc-pVDZ engrad single points for the H2O molecule. single point energies were independently checked using the original wavels code |
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All-electron MP2 6-31G** geometry optimization of water |
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CASSCF/6-31G** energy point |
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UHF-CCSD(T) cc-pVDZ frozen-core energy for the \(^2\Sigma^+\) state of the CN radical, with Z-matrix input. |
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RHF/cc-pvdz-decontract HCl single-point energy Testing the in line -decontract option for basis sets |
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Generation of NBO file |
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td-uhf test on triplet states of methylene (rpa) |
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RHF orbitals and density for water. |
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Unrestricted DF-DCT ODC-12 gradient for O2 with cc-pVTZ/cc-pVTZ-RI standard/auxiliary basis set |
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DF-OMP2.5 cc-pVDZ energy for the H2O+ cation |
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6-31G** H2O Test CISD Energy Point |
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Example SAPT computation for ethene*ethine (i.e., ethylene*acetylene), test case 16 from the S22 database |
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RHF orbitals and density for water. |
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ROHF 6-31G** energy of the \(^{3}B_1\) state of CH2, with Z-matrix input. The occupations are specified explicitly. |
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Electrostatic potential and electric field evaluated on a grid around water. |
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This test case shows an example of running and analyzing an FI-SAPT0/jun-cc-pvdz computation for 2,4-pentanediol (targeting the intramolecular hydrogen bond between the two hydroxyl groups) |
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HF/cc-pVDZ many body energies of an arbitrary noble gas trimer complex Size vs cost tradeoff is rough here |
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DF-SCF cc-pVDZ multipole moments of benzene, up to 7th order and electrostatic potentials evaluated at the nuclear coordinates |
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DF-OMP2.5 cc-pVDZ gradients for the H2O+ cation. |
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Sample UHF/6-31G** CH2 computation |
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cc-pvdz H2O Test ACPF Energy/Properties |
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Test FNO-DF-CCSD(T) energy |
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MBIS calculation on NaCl |
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DF-OMP3 cc-pVDZ gradients for the H2O molecule. |
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DF-CCSDL cc-pVDZ energy for the H2O molecule. |
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Triple and Singlet Oxygen energy SOSCF, also tests non-symmetric density matrices |
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Test QCISD(T) for H2O/cc-pvdz Energy |
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DCT calculation for the triplet O2 using DC-06 and DC-12. Only two-step algorithm is tested. |
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SAPT(DFT) aug-cc-pVDZ interaction energy between Ne and Ar atoms. |
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CCSD dipole with user-specified basis set |
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Computation of VMFC-corrected water trimer gradient (geometry from J. Chem. Theory Comput. 11, 2126-2136 (2015)) |
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A demonstration of mixed Cartesian/ZMatrix geometry specification, using variables, for the benzene-hydronium complex. Atoms can be placed using ZMatrix coordinates, whether they belong to the same fragment or not. Note that the Cartesian specification must come before the ZMatrix entries because the former define absolute positions, while the latter are relative. |
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CASSCF/6-31G** energy point |
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He2+ FCI/cc-pVDZ Transition Dipole Moment |
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RHF STO-3G (Cartesian) and cc-pVDZ (spherical) water Hessian test, against Psi3 reference values. |
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TCSCF cc-pVDZ energy of asymmetrically displaced ozone, with Z-matrix input. |
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MBIS calculation on ZnO |
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Tests CAM gradients with and without XC pieces to narrow grid error |
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MP2.5 cc-pVDZ gradient for the H2O molecule. |
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apply linear fragmentation algorithm to a water cluster |
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Test case for Binding Energy of C4H5N (Pyrrole) with CO2 using MP2/def2-TZVPP |
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Frozen-core CCSD(T)/cc-pVDZ on C4H4N anion with disk ao algorithm |
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cc-pvdz H2O Test coupled-pair CISD against DETCI CISD |
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DF-MP2 cc-pVDZ gradient for the NO molecule. |
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6-31G* C2 Test RASCI Energy Point, testing two different ways of specifying the active space, either with the ACTIVE keyword, or with RAS1, RAS2, RESTRICTED_DOCC, and RESTRICTED_UOCC |
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integral conventional REMP/cc-pVDZ energies for the H2O molecule. results were independently verified against the initial wavels implementation |
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BH single points, checking that program can run multiple instances of DETCI in a single input, without an intervening clean() call |
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OMP2 cc-pVDZ energy with ROHF initial guess orbitals for the NO radical |
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RHF-CC2-LR/cc-pVDZ static polarizabilities of HOF molecule. |
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SCF STO-3G finite-difference tests |
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DF-MP2 cc-pVDZ frozen core gradient of benzene, computed at the DF-SCF cc-pVDZ geometry |
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File retention, docc, socc, and bond distances specified explicitly. |
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A very quick correctness test of F-SAPT (see fsapt1 for a real example) |
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OMP2 cc-pVDZ gradient for the NO radical |
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UHF Dipole Polarizability Test |
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UHF-CCSD/cc-pVDZ \(^{3}B_1\) CH2 geometry optimization via analytic gradients |
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td-wb97x singlet excitation energies of methylene (tda) |
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UHF->UHF stability analysis test for BH with cc-pVDZ Test direct SCF with and without symmetry, test PK without symmetry |
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RHF Linear Exchange Algorithm test for water |
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Symmetry tests for a range of molecules. This doesn’t actually compute any energies, but serves as an example of the many ways to specify geometries in Psi4. |
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RASCI/6-31G** H2O Energy Point |
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OLCCD cc-pVDZ energy for the H2O molecule. |
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DFT custom functional test |
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RHF 6-31G** energy of water, using the MCSCF module and Z-matrix input. |
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Test SCF dipole derivatives against old Psi3 reference values |
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td-uhf test on triplet states of methylene (tda), wfn passing |
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UFH and B3LYP cc-pVQZ properties for the CH2 molecule. |
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Single-point gradient, analytic and via finite-differences of 2-1A1 state of H2O with EOM-CCSD |
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OMP2 cc-pVDZ energy for the NO radical |
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DFT Functional Test all values update for new BraggSlater radii |
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DF-A-CCSD(T) cc-pVDZ energy for the NH molecule. |
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Various constrained energy minimizations of HOOH with cc-pvdz RHF. Cartesian-coordinate constrained optimizations of HOOH in Cartesians. |
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ROHF-EOM-CCSD/DZ analytic gradient lowest \(^{2}A_1\) excited state of H2O+ (B1 excitation) |
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Analytic vs. finite difference DF-SCF frequency test for water. |
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Test of SAD/Cast-up (mainly not dying due to file weirdness) |
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SAPT0 aug-cc-pVDZ computation of the benzene-methane interaction energy, using the aug-pVDZ-JKFIT DF basis for SCF, the aug-cc-pVDZ-RI DF basis for SAPT0 induction and dispersion, and the aug-pVDZ-JKFIT DF basis for SAPT0 electrostatics and induction. This example uses frozen core as well as asyncronous I/O while forming the DF integrals and CPHF coefficients. |
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Test of SFX2C-1e on water uncontracted cc-pVDZ-DK The reference numbers are from Lan Cheng’s implementation in Cfour |
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Various constrained energy minimizations of HOOH with cc-pvdz RHF. Cartesian-coordinate constrained optimizations of HOOH in internals. |
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Computation of CP-corrected water trimer gradient (geometry from J. Chem. Theory Comput. 11, 2126-2136 (2015)) |
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Various extrapolated optimization methods for the H2 molecule |
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EOM-CC3(ROHF) on CH radical with user-specified basis and properties for particular root |
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LCCD cc-pVDZ gradient for the H2O molecule. |
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Transition-state optimizations of HOOH to both torsional transition states. |
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wB97X-D test for a large UKS molecule update ref gradient due to new BraggSlater radii |
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DC-06 calculation for the O2 molecule (triplet ground state). This performs geometry optimization using two-step and simultaneous solution of the response equations for the analytic gradient. |
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DF-OMP3 cc-pVDZ energy for the H2O+ cation |
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An example of using BLAS and LAPACK calls directly from the Psi input file, demonstrating matrix multiplication, eigendecomposition, Cholesky decomposition and LU decomposition. These operations are performed on vectors and matrices provided from the Psi library. |
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Tests SAPT0-D corrections, with a variety of damping functions/parameters |
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Computation of VMFC-corrected HF dimer Hessian |
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Water-Argon complex with ECP present; check of energies and forces. |
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OMP2 cc-pVDZ energy for the H2O molecule. |
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DF-CCSD cc-pVDZ gradient for the NH molecule. |
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density fitted REMP/cc-pVDZ energies for the CO2 molecule. |
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Test if the the guess read in the same basis converges. |
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check all variety of options parsing |
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usapt example with empty beta |
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RHF cc-pVDZ energy for water, automatically scanning the symmetric stretch and bending coordinates using Python’s built-in loop mechanisms. The geometry is specified using a Z-matrix with variables that are updated during the potential energy surface scan, and then the same procedure is performed using polar coordinates, converted to Cartesian coordinates. |
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DC-06, DC-12, ODC-06 and ODC-12 calculation for the He dimer. This performs a simultaneous update of the orbitals and cumulant, using DIIS extrapolation. Four-virtual integrals are handled in the MO Basis. |
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Test case for some of the PSI4 out-of-core codes. The code is given only 2.0 MB of memory, which is insufficient to hold either the A1 or B2 blocks of an ovvv quantity in-core, but is sufficient to hold at least two copies of an oovv quantity in-core. |
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Patch of a glycine with a methyl group, to make alanine, then DF-SCF energy calculation with the cc-pVDZ basis set |
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Cholesky decomposed REMP/cc-pVDZ energies for the CO2 molecule. |
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CCSD/cc-pVDZ optical rotation calculation (length gauge only) on Z-mat H2O2 |
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Database calculation, so no molecule section in input file. Portions of the full databases, restricted by subset keyword, are computed by sapt0 and dfmp2 methods. |
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CASSCF/6-31G** energy point |
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SAPT0 open-shell computation of H2O-HO2 interaction energy First with cc-pVDZ and density fitted integrals with UHF Then with 6-31g and direct integrals, except for dispersion that is computed with cc-pVDZ-ri density fitting with UHF. |
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SCF STO-3G finite-differences frequencies from gradients for H2O |
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Various constrained energy minimizations of HOOH with cc-pvdz RHF. For “fixed” coordinates, the final value is provided by the user. |
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BH-H2+ FCI/cc-pVDZ Transition Dipole Moment |
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UHF gradient for a one-electron system (no beta electrons). |
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RHF-ODC-12 analytic gradient computations for H2O use AO_BASIS=DISK and AO_BASIS=NONE, respectively. RHF-ODC-06 analytic gradient computations for H2O use AO_BASIS=DISK and AO_BASIS=NONE, respectively. |
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FSAPT with external charge on trimer |
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Vibrational and thermo analysis of water trimer (geometry from J. Chem. Theory Comput. 11, 2126-2136 (2015)) |
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This test case shows an example of running and analyzing a difference F-SAPT0/jun-cc-pvdz procedure for phenol dimer from the S22 database. |
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RI-SCF cc-pVTZ energy of water, with Z-matrix input and cc-pVTZ-RI auxilliary basis. |
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DC-06 calculation for the He dimer. This performs a two-step update of the orbitals and cumulant, using DIIS extrapolation. Four-virtual integrals are handled in the MO Basis. |
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ROHF-CCSD cc-pVDZ energy for the \(^2\Sigma^+\) state of the CN radical |
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SAPT0 aug-cc-pVTZ computation of the charge transfer energy of the water dimer. |
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SCS-OMP3 cc-pVDZ geometry optimization for the H2O molecule. |
|
ROHF-CCSD(T) cc-pVDZ energy for the \(^2\Sigma^+\) state of the CN radical, with Z-matrix input. |
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This test case shows an example of running and analyzing a standard F-SAPT0/jun-cc-pvdz procedure for phenol dimer from the S22 database. |
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MP2 with a PBE0 reference computation |
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RHF-CCSD(T) cc-pVQZ frozen-core energy of the BH molecule, with Cartesian input. After the computation, the checkpoint file is renamed, using the PSIO handler. |
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Check flavors of B3LYP (b3lyp3/b3lyp5) against other programs |
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ADIIS test case, from 10.1063/1.3304922 |
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MBIS calculation on H2O |
|
FSAPT with external charge on dimer |
|
testing aligner on enantiomers based on Table 1 of 10.1021/ci100219f aka J Chem Inf Model 2010 50(12) 2129-2140 |
|
DCT calculation for the HF+ using DC-06 functional. This performs both two-step and simultaneous update of the orbitals and cumulant using DIIS extrapolation. Four-virtual integrals are first handled in the MO Basis for the first two energy computations. In the next two the ao_basis=disk algorithm is used, where the transformation of integrals for four-virtual case is avoided. The computation is then repeated using the DC-12 functional with the same algorithms. |
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DF-OMP3 cc-pVDZ gradients for the H2O+ cation. |
|
Test that Python Molecule class processes geometry like psi4 Molecule class. |
|
SAPT calculation on bimolecular complex where monomers are unspecified so driver auto-fragments it. Basis set and auxiliary basis sets are assigned by atom type. |
|
check SP basis Fortran exponent parsing |
|
A test of the basis specification. A benzene atom is defined using a ZMatrix containing dummy atoms and various basis sets are assigned to different atoms. The symmetry of the molecule is automatically lowered to account for the different basis sets. |
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SCF with various combinations of pk/density-fitting, castup/no-castup, and spherical/cartesian settings. Demonstrates that puream setting is getting set by orbital basis for all df/castup parts of calc. Demonstrates that answer doesn’t depend on presence/absence of castup. Demonstrates (by comparison to castup2) that output file doesn’t depend on options (scf_type) being set global or local. This input uses local. |
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This test case shows an example of running the I-SAPT0/jun-cc-pVDZ computation for 2,4-pentanediol (targeting the intramolecular hydrogen bond between the two hydroxyl groups) The SIAO1 link partitioning algorithm is used. An F-SAPT partitioning follows I-SAPT. |
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External potential calculation involving a TIP3P water and a QM water. Finite different test of the gradient is performed to validate forces. |
|
test scf castup with custom basis sets |
|
OMP3 cc-pVDZ gradient for the H2O molecule. |
|
comparison of DF-MP2 and DLPNO-MP2 |
|
6-31G H2O Test FCI Energy Point |
|
Tests RHF/ROHF/UHF SCF gradients |
|
External potential calculation involving a TIP3P water and a QM water for DFMP2. Finite different test of the gradient is performed to validate forces. |
|
OMP2 cc-pVDZ gradient for the H2O molecule. |
|
OMP3 cc-pCVDZ energy with B3LYP initial guess for the NO radical |
|
wB97X-D cc-pVDZ gradient of S22 HCN update df/pk_ref values due to new BraggSlater radii |
|
CCSD/cc-pVDZ optical rotation calculation (both gauges) on Cartesian H2O2 |
|
Various constrained energy minimizations of HOOH with cc-pvdz RHF Internal-coordinate constraints in internal-coordinate optimizations. |
|
SOS-OMP3 cc-pVDZ geometry optimization for the H2O molecule. |
|
analog of fsapt-ext-abc with molecule and external potentials in Bohr |
|
Mk-MRCCSD single point. \(^3 \Sigma ^-\) O2 state described using the Ms = 0 component of the triplet. Uses ROHF triplet orbitals. |
|
ROHF-CCSD(T) cc-pVDZ frozen-core energy for the \(^2\Sigma^+\) state of the CN radical, with Cartesian input. |
|
Frequencies for H2O B3LYP/6-31G* at optimized geometry |
|
SAPT0 aug-cc-pVDZ computation of the water-water interaction energy, using the three SAPT codes. |
|
Test fnocc with linear dependencies |
|
RHF Density Matrix based-Integral Screening Test for water |
|
DF-MP2 cc-pVDZ gradients for the H2O molecule. |
|
MP3 cc-pVDZ gradient for the H2O molecule. |
|
Benzene Dimer Out-of-Core HF/cc-pVDZ |
|
mtd/basis syntax examples |
|
CC3(ROHF)/cc-pVDZ H2O \(R_e\) geom from Olsen et al., JCP 104, 8007 (1996) |
|
check mixing ECP and non-ECP orbital/fitting basis sets in a session |
|
Gradient regularized asymptotic correction (GRAC) test. |
|
Test SFX2C-1e with a static electric field on He aug-cc-pVTZ |
|
ROHF-CCSD cc-pVDZ frozen-core energy for the \(^2\Sigma^+\) state of the CN radical, with Cartesian input. |
|
6-31G(d) optimization of SF4 starting from linear bond angle that is not linear in the optimized structure but is in a symmetry plane of the molecule. |
|
SOS-OMP2 cc-pVDZ geometry optimization for the H2O molecule. |
|
DF-OMP2 cc-pVDZ gradients for the H2O molecule. |
|
Sample HF/cc-pVDZ H2O computation |
|
SAPT(DFT) aug-cc-pVDZ interaction energy between Ne and Ar atoms. |
|
SCF level shift on an ROHF computation |