# PSI Variables by Alpha¶

Note

Lowercase letters in PSI variable names represent portions of the variable name that vary by root number, calculation order, etc. See text for fuller description.

- [T] CORRECTION ENERGY¶
The coupled-cluster bracket perturbative triples correction [Eh].

- (T) CORRECTION ENERGY¶
The coupled-cluster perturbative triples correction [Eh].

- (AT) CORRECTION ENERGY¶
- A-(T) CORRECTION ENERGY¶
The coupled-cluster asymmetric perturbative triples correction [Eh].

- AAA (T) CORRECTION ENERGY¶
- AAB (T) CORRECTION ENERGY¶
- ABB (T) CORRECTION ENERGY¶
- BBB (T) CORRECTION ENERGY¶
Spin components of the UHF-based coupled-cluster perturbative triples correction [Eh].

- ACPF DIPOLE¶
Dipole array [e a0] for the averaged coupled-pair functional level of theory, (3,).

- ACPF DIPOLE X¶
- ACPF DIPOLE Y¶
- ACPF DIPOLE Z¶
The three components of the dipole [Debye] for the averaged coupled-pair functional level of theory. Deprecated in favor of

`ACPF DIPOLE`

.

- ACPF QUADRUPOLE¶
Redundant quadrupole array [e a0^2] for the averaged coupled-pair functional level of theory, (3, 3).

- ACPF QUADRUPOLE XX¶
- ACPF QUADRUPOLE XY¶
- ACPF QUADRUPOLE XZ¶
- ACPF QUADRUPOLE YY¶
- ACPF QUADRUPOLE YZ¶
- ACPF QUADRUPOLE ZZ¶
The six components of the quadrupole [Debye Ang] for the averaged coupled-pair functional level of theory. Deprecated in favor of

`ACPF QUADRUPOLE`

.

- ACPF TOTAL ENERGY¶
- ACPF CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the averaged coupled-pair functional level of theory.

- AQCC DIPOLE¶
Dipole array [e a0] for the averaged quadratic coupled-cluster level of theory, (3,).

- AQCC DIPOLE X¶
- AQCC DIPOLE Y¶
- AQCC DIPOLE Z¶
The three components of the dipole [Debye] for the averaged quadratic coupled-cluster level of theory. Deprecated in favor of

`AQCC DIPOLE`

.

- AQCC QUADRUPOLE¶
Redundant quadrupole array [e a0^2] for the averaged quadratic coupled-cluster level of theory, (3, 3).

- AQCC QUADRUPOLE XX¶
- AQCC QUADRUPOLE XY¶
- AQCC QUADRUPOLE XZ¶
- AQCC QUADRUPOLE YY¶
- AQCC QUADRUPOLE YZ¶
- AQCC QUADRUPOLE ZZ¶
The six components of the quadrupole [Debye Ang] for the averaged quadratic coupled-cluster level of theory. Deprecated in favor of

`AQCC QUADRUPOLE`

.

- AQCC TOTAL ENERGY¶
- AQCC CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the averaged quadratic coupled-cluster level of theory.

- BRUECKNER CONVERGED¶
Value 1 (0) when the Brueckner orbitals have (have not) converged.

- CBS TOTAL ENERGY¶
- CBS CORRELATION ENERGY¶
- CBS REFERENCE ENERGY¶
The total electronic energy [Eh] and its breakdown into reference total energy [Eh] and correlation correction components [Eh] for the compound method requested through cbs().

- CC ROOT n DIPOLE¶
Dipole array [e a0] for the requested coupled cluster level of theory and root

*n*(number starts at GS = 0), (3,).

- CC ROOT n DIPOLE X¶
- CC ROOT n DIPOLE Y¶
- CC ROOT n DIPOLE Z¶
The three components of the dipole [Debye] for the requested coupled cluster level of theory and root

*n*(number starts at GS = 0). Deprecated in favor of`CC ROOT n DIPOLE`

.

- CC ROOT n QUADRUPOLE¶
Redundant quadrupole array [e a0^2] for the requested coupled cluster level of theory and root

*n*(number starts at GS = 0), (3, 3).

- CC ROOT n QUADRUPOLE XX¶
- CC ROOT n QUADRUPOLE XY¶
- CC ROOT n QUADRUPOLE XZ¶
- CC ROOT n QUADRUPOLE YY¶
- CC ROOT n QUADRUPOLE YZ¶
- CC ROOT n QUADRUPOLE ZZ¶
The six components of the quadrupole [Debye Ang] for the requested coupled cluster level of theory and root

*n*(numbering starts at GS = 0). Deprecated in favor of`CC ROOT n QUADRUPOLE`

.

- CC ROOT n TOTAL ENERGY¶
- CC ROOT n CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the requested coupled cluster level of theory and root

*n*(numbering starts at GS = 0).

- CC T1 DIAGNOSTIC¶
- CC D1 DIAGNOSTIC¶
- CC NEW D1 DIAGNOSTIC¶
- CC D2 DIAGNOSTIC¶
Diagnostic of multireference character.

- CC2 TOTAL ENERGY¶
- CC2 CORRELATION ENERGY¶
- CC3 TOTAL ENERGY¶
- CC3 CORRELATION ENERGY¶
- CC4 TOTAL ENERGY¶
- CC4 CORRELATION ENERGY¶
- CCnn TOTAL ENERGY¶
- CCnn CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the requested approximate coupled-cluster (CC2, CC3, up to CC

*nn*) level of theory.

- CC DIPOLE¶
Dipole array [e a0] for the requested coupled cluster level of theory and root, (3,).

- CC DIPOLE X¶
- CC DIPOLE Y¶
- CC DIPOLE Z¶
The three components of the dipole [Debye] for the requested coupled cluster level of theory and root. Deprecated in favor of

`CC DIPOLE`

.

- CC2 DIPOLE POLARIZABILITY @ xNM¶
The dipole polarizability [au] calculated at the CC2 level for a given (x) wavelength, (x) rounded to nearest integer.

- CC2 SPECIFIC ROTATION (LEN) @ xNM¶
The specific rotation [deg/(dm (g/cm^3))] calculated at the CC2 level in the length gauge for a given (x) wavelength, (x) rounded to nearest integer.

- CC2 SPECIFIC ROTATION (VEL) @ xNM¶
The specific rotation [deg/(dm (g/cm^3))] calculated at the CC2 level in the velocity gauge for a given (x) wavelength, (x) rounded to nearest integer.

- CC2 SPECIFIC ROTATION (MVG) @ xNM¶
The specific rotation [deg/(dm (g/cm^3))] calculated at the CC2 level in the modified velocity gauge for a given (x) wavelength, (x) rounded to nearest integer.

- CC QUADRUPOLE XX¶
- CC QUADRUPOLE XY¶
- CC QUADRUPOLE XZ¶
- CC QUADRUPOLE YY¶
- CC QUADRUPOLE YZ¶
- CC QUADRUPOLE ZZ¶
The six components of the quadrupole [Debye Ang] for the requested coupled cluster level of theory and root.

- CCD TOTAL ENERGY¶
- CCD CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the coupled-cluster doubles level of theory.

- CCSD PAIR ENERGIES¶
The restricted-reference pair energies for coupled-cluster singles and doubles level of theory. Size number of active doubly occupied orbitals, square.

- CCSD TOTAL ENERGY¶
- CCSD CORRELATION ENERGY¶
- CCSDT TOTAL ENERGY¶
- CCSDT CORRELATION ENERGY¶
- CCSDTQ TOTAL ENERGY¶
- CCSDTQ CORRELATION ENERGY¶
- CCn TOTAL ENERGY¶
- CCn CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the requested full coupled-cluster (CCSD, CCSDT, up to CC

*n*) level of theory.

- CCSD(T) TOTAL ENERGY¶
- CCSD(T) CORRELATION ENERGY¶
- CCSD(AT) TOTAL ENERGY¶
- CCSD(AT) CORRELATION ENERGY¶
- A-CCSD(T) TOTAL ENERGY¶
- A-CCSD(T) CORRELATION ENERGY¶
- CCSDT(Q) TOTAL ENERGY¶
- CCSDT(Q) CORRELATION ENERGY¶
- CC(n-1)(n) TOTAL ENERGY¶
- CC(n-1)(n) CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the perturbatively corrected coupled-cluster (CCSD(T), A-CCSD(T) = CCSD(AT), CCSDT(Q), up to CC(

*n*-1)(*n*) level of theory.

- CCSDT-1a TOTAL ENERGY¶
- CCSDT-1a CORRELATION ENERGY¶
- CCSDTQ-1a TOTAL ENERGY¶
- CCSDTQ-1a CORRELATION ENERGY¶
- CCn-1a TOTAL ENERGY¶
- CCn-1a CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the approximate coupled-cluster (CCSD(T)-1a, CCSDT(Q)-1a, up to CC

*n*-1a) level of theory.

- CCSDT-1b TOTAL ENERGY¶
- CCSDT-1b CORRELATION ENERGY¶
- CCSDTQ-1b TOTAL ENERGY¶
- CCSDTQ-1b CORRELATION ENERGY¶
- CCn-1b TOTAL ENERGY¶
- CCn-1b CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the approximate coupled-cluster (CCSD(T)-1b, CCSDT(Q)-1b, up to CC

*n*-1b) level of theory.

- CCSDT-3 TOTAL ENERGY¶
- CCSDT-3 CORRELATION ENERGY¶
- CCSDTQ-3 TOTAL ENERGY¶
- CCSDTQ-3 CORRELATION ENERGY¶
- CCn-3 TOTAL ENERGY¶
- CCn-3 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the approximate coupled-cluster (CCSD(T)-3, CCSDT(Q)-3, up to CC

*n*-3) level of theory.

- CCSD(T)_L TOTAL ENERGY¶
- CCSD(T)_L CORRELATION ENERGY¶
- CCSDT(Q)_L TOTAL ENERGY¶
- CCSDT(Q)_L CORRELATION ENERGY¶
- CC(n-1)(n)_L TOTAL ENERGY¶
- CC(n-1)(n)_L CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the approximate coupled-cluster (CCSD(T)_L, CCSDT(Q)_L, up to CC(

*n*-1)(*n*)L level of theory.

- CCSDT(Q)/A TOTAL ENERGY¶
- CCSDT(Q)/A CORRELATION ENERGY¶
- CCSDT(Q)/B TOTAL ENERGY¶
- CCSDT(Q)/B CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the modified CCSDT(Q) level of theory.

- CCSD DIPOLE POLARIZABILITY @ xNM¶
The dipole polarizability [au] calculated at the CCSD level for a given (x) wavelength, (x) rounded to nearest integer.

- CCSD SPECIFIC ROTATION (LEN) @ xNM¶
The specific rotation [deg/(dm (g/cm^3))] calculated at the CCSD level in the length gauge for a given (x) wavelength, (x) rounded to nearest integer.

- CCSD SPECIFIC ROTATION (VEL) @ xNM¶
The specific rotation [deg/(dm (g/cm^3))] calculated at the CCSD level in the velocity gauge for a given (x) wavelength, (x) rounded to nearest integer.

- CCSD SPECIFIC ROTATION (MVG) @ xNM¶
The specific rotation [deg/(dm (g/cm^3))] calculated at the CCSD level in the modified velocity gauge for a given (x) wavelength, (x) rounded to nearest integer.

- CEPA(0) DIPOLE¶
Dipole array [e a0] for the coupled electron pair approximation variant 0 level of theory, (3,).

- CEPA(0) DIPOLE X¶
- CEPA(0) DIPOLE Y¶
- CEPA(0) DIPOLE Z¶
The three components of the dipole [Debye] for the coupled electron pair approximation variant 0 level of theory. Deprecated in favor of

`CEPA(0) DIPOLE`

.

- CEPA(0) QUADRUPOLE¶
Redundant quadrupole array [e a0^2] for the coupled electron pair approximation variant 0 level of theory, (3, 3).

- CEPA(0) QUADRUPOLE XX¶
- CEPA(0) QUADRUPOLE XY¶
- CEPA(0) QUADRUPOLE XZ¶
- CEPA(0) QUADRUPOLE YY¶
- CEPA(0) QUADRUPOLE YZ¶
- CEPA(0) QUADRUPOLE ZZ¶
The six components of the quadrupole [Debye Ang] for the coupled electron pair approximation variant 0 level of theory. Deprecated in favor of

`CEPA(0) QUADRUPOLE`

.

- CEPA(0) TOTAL ENERGY¶
- CEPA(0) CORRELATION ENERGY¶
- CEPA(1) TOTAL ENERGY¶
- CEPA(1) CORRELATION ENERGY¶
- CEPA(2) TOTAL ENERGY¶
- CEPA(2) CORRELATION ENERGY¶
- CEPA(3) TOTAL ENERGY¶
- CEPA(3) CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the requested variant of coupled electron pair approximation level of theory.

- CFOUR ERROR CODE¶
The non-zero return value from a Cfour execution.

- CI DIPOLE¶
Dipole array [e a0] for the requested configuration interaction level of theory, (3,).

- CI DIPOLE X¶
- CI DIPOLE Y¶
- CI DIPOLE Z¶
The three components of the dipole [Debye] for the requested configuration interaction level of theory and root. Deprecated in favor of

`CI DIPOLE`

.

- CI QUADRUPOLE¶
Redundant quadrupole array [e a0^2] for the requested configuration interaction level of theory, (3, 3).

- CI QUADRUPOLE XX¶
- CI QUADRUPOLE XY¶
- CI QUADRUPOLE XZ¶
- CI QUADRUPOLE YY¶
- CI QUADRUPOLE YZ¶
- CI QUADRUPOLE ZZ¶
The six components of the quadrupole [Debye Ang] for the requested configuration interaction level of theory and root. Deprecated in favor of

`CI QUADRUPOLE`

.

- CI ROOT n -> ROOT m DIPOLE¶
Transition dipole array [e a0] between roots

*n*and*m*for the requested configuration interaction level of theory, (3,).

- CI ROOT n -> ROOT m DIPOLE X¶
- CI ROOT n -> ROOT m DIPOLE Y¶
- CI ROOT n -> ROOT m DIPOLE Z¶
The three components of the transition dipole [Debye] between roots

*n*and*m*for the requested configuration interaction level of theory. Deprecated in favor of`CI ROOT n -> ROOT m DIPOLE`

.

- CI ROOT n -> ROOT m QUADRUPOLE¶
Redundant transition quadrupole array [e a0^2] between roots

*n*and*m*for the requested configuration interaction level of theory, (3, 3).

- CI ROOT n -> ROOT m QUADRUPOLE XX¶
- CI ROOT n -> ROOT m QUADRUPOLE XY¶
- CI ROOT n -> ROOT m QUADRUPOLE XZ¶
- CI ROOT n -> ROOT m QUADRUPOLE YY¶
- CI ROOT n -> ROOT m QUADRUPOLE YZ¶
- CI ROOT n -> ROOT m QUADRUPOLE ZZ¶
The three components of the transition quadrupole [Debye Ang] between roots

*n*and*m*for the requested configuration interaction level of theory. Deprecated in favor of`CI ROOT n -> ROOT m QUADRUPOLE`

.

- CI ROOT n DIPOLE¶
Dipole array [e a0] for the requested configuration interaction level of theory and root

*n*, (3,).

- CI ROOT n DIPOLE X¶
- CI ROOT n DIPOLE Y¶
- CI ROOT n DIPOLE Z¶
The three components of the dipole [Debye] for the requested configuration interaction level of theory and root

*n*. Deprecated in favor of`CI ROOT n DIPOLE`

.

- CI ROOT n QUADRUPOLE¶
Redundant quadrupole array [e a0^2] for the requested configuration interaction level of theory and root

*n*, (3, 3).

- CI ROOT n QUADRUPOLE XX¶
- CI ROOT n QUADRUPOLE XY¶
- CI ROOT n QUADRUPOLE XZ¶
- CI ROOT n QUADRUPOLE YY¶
- CI ROOT n QUADRUPOLE YZ¶
- CI ROOT n QUADRUPOLE ZZ¶
The six components of the quadrupole [Debye Ang] for the requested configuration interaction level of theory and root

*n*. Deprecated in favor of`CI ROOT n QUADRUPOLE`

.

- CI ROOT n TOTAL ENERGY¶
- CI ROOT n CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the requested configuration interaction level of theory and root

*n*(numbering starts at 0).

- CI STATE-AVERAGED TOTAL ENERGY¶
- CI STATE-AVERAGED CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for state-averaged CI/CASSCF levels of theory.

- CI TOTAL ENERGY¶
- CI CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the requested configuration interaction level of theory and root.

- CISD DIPOLE¶
Dipole array [e a0] for the configuration interaction singles and doubles level of theory, (3,).

- CISD DIPOLE X¶
- CISD DIPOLE Y¶
- CISD DIPOLE Z¶
The three components of the dipole [Debye] for the configuration interaction singles and doubles level of theory and root. Deprecated in favor of

`CISD DIPOLE`

.

- CISD QUADRUPOLE¶
Redundant quadrupole array [e a0^2] for the configuration interaction singles and doubles level of theory, (3, 3).

- CISD QUADRUPOLE XX¶
- CISD QUADRUPOLE XY¶
- CISD QUADRUPOLE XZ¶
- CISD QUADRUPOLE YY¶
- CISD QUADRUPOLE YZ¶
- CISD QUADRUPOLE ZZ¶
The six components of the quadrupole [Debye Ang] for the configuration interaction singles and doubles level of theory and root. Deprecated in favor of

`CISD QUADRUPOLE`

.

- CISD TOTAL ENERGY¶
- CISD CORRELATION ENERGY¶
- CISDT TOTAL ENERGY¶
- CISDT CORRELATION ENERGY¶
- CISDTQ CORRELATION ENERGY¶
- CISDTQ TOTAL ENERGY¶
- CIn CORRELATION ENERGY¶
- CIn TOTAL ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the labeled configuration interaction level of theory and root.

*n*is CI order for*n*> 4.

- CP-CORRECTED 2-BODY INTERACTION ENERGY¶
The interaction energy [Eh] considering only two-body interactions, computed with counterpoise correction. Related variable

`UNCP-CORRECTED 2-BODY INTERACTION ENERGY`

.\[E_{\text{IE}} = E_{dimer} - \sum_{monomer}^{n}{E_{monomer}^{\text{CP}}}\]

- CURRENT CORRELATION ENERGY¶
The correlation energy [Eh] corresponding to the

`CURRENT ENERGY`

variable.

- CURRENT ENERGY¶
The total electronic energy [Eh] of the most recent stage of a calculation (frequently overwritten). This is the quantity tracked by the geometry optimizer.

- CURRENT REFERENCE ENERGY¶
The total electronic energy [Eh] of the reference stage corresponding to the

`CURRENT ENERGY`

variable.

- CURRENT DIPOLE¶
The total dipole [e a0] of the most recent stage of a calculation (frequently overwritten), (3,).

- CURRENT GRADIENT¶
The total electronic gradient [E_h/a0] of the most recent stage of a calculation (frequently overwritten). This is the quantity tracked by the geometry optimizer, ({nat}, 3).

- CURRENT DIPOLE GRADIENT¶
The derivative of the dipole with respect to nuclear perturbations [E_h a0/u] = [(e a0/a0)^2/u] as a degree-of-freedom by dipole component array, (3 * {nat}, 3).

- CURRENT HESSIAN¶
The total electronic Hessian [E_h/a0/a0] of the most recent stage of a calculation, (3 * {nat}, 3 * {nat}).

- CUSTOM SCS-MP2 TOTAL ENERGY¶
- CUSTOM SCS-MP2 CORRELATION ENERGY¶
Changeable quantities based on options. The total electronic energy [Eh] and correlation energy component [Eh] for the MP2-like method formed by any reweighting of

`MP2 DOUBLES ENERGY`

for opposite-spin and same-spin contributions, with any singles carried along. Depending on weights, may equal any of MP2, SCS-MP2, SCS(N)-MP2, etc. quantities. Contrast with`SCS-MP2 TOTAL ENERGY`

.

- CUSTOM SCS-MP2.5 TOTAL ENERGY¶
- CUSTOM SCS-MP2.5 CORRELATION ENERGY¶
- CUSTOM SCS-MP3 TOTAL ENERGY¶
- CUSTOM SCS-MP3 CORRELATION ENERGY¶
- CUSTOM SCS-LCCD TOTAL ENERGY¶
- CUSTOM SCS-LCCD CORRELATION ENERGY¶
- CUSTOM SCS-OMP2 TOTAL ENERGY¶
- CUSTOM SCS-OMP2 CORRELATION ENERGY¶
- CUSTOM SCS-OMP2.5 TOTAL ENERGY¶
- CUSTOM SCS-OMP2.5 CORRELATION ENERGY¶
- CUSTOM SCS-OMP3 TOTAL ENERGY¶
- CUSTOM SCS-OMP3 CORRELATION ENERGY¶
- CUSTOM SCS-OLCCD TOTAL ENERGY¶
- CUSTOM SCS-OLCCD CORRELATION ENERGY¶
Changeable quantities based on options. The total electronic energy [Eh] and correlation energy component [Eh] for the method formed by any reweighting of the named

for opposite-spin and same-spin contributions, with any singles carried along. Contrast with :samp`SCS-{method} TOTAL ENERGY`.*method*DOUBLES ENERGY

- db_name DATABASE MEAN ABSOLUTE DEVIATION¶
The mean absolute deviation [kcal mol

^{-1}] of the requested method*name*from the stored reference values for the requested reactions in database*db_name*. If no reference is available, this will be a large and nonsensical value.\[\frac{1}{n}\sum_{rxn}^{n}{| \textsf{\textsl{name}}_{rxn}-\text{REF}_{rxn} | }\]

- db_name DATABASE MEAN SIGNED DEVIATION¶
The mean deviation [kcal mol

^{-1}] of the requested method*name*from the stored reference values for the requested reactions in database*db_name*. If no reference is available, this will be a large and nonsensical value.\[\frac{1}{n}\sum_{rxn}^{n}{\textsf{\textsl{name}}_{rxn}-\text{REF}_{rxn}}\]

- db_name DATABASE ROOT-MEAN-SQUARE DEVIATION¶
The rms deviation [kcal mol

^{-1}] of the requested method*name*from the stored reference values for the requested reactions in database*db_name*. If no reference is available, this will be a large and nonsensical value.\[\sqrt{\frac{1}{n}\sum_{rxn}^{n}{(\textsf{\textsl{name}}_{rxn}-\text{REF}_{rxn})^2}}\]

- DCT LAMBDA ENERGY¶
An energy term in density cumulant theory [Eh]. This term is the 2-electron cumulant’s contribution contribution to the reduced density matrix energy expression. Not recommended for interpretative use except by reduced density matrix specialists.

- DCT SCF ENERGY¶
An energy term in density cumulant theory [Eh]. This term is the 1-electron reduced density matrix (1RDM) contribution to the reduced density matrix energy expression, plus the contribution of the antisymmetrized product of 1RDMs. Not recommended for interpretative use except by reduced density matrix specialists.

- DCT THREE-PARTICLE ENERGY¶
The three-particle correlation energy correction [Eh] in density cumulant theory, akin to

`(T) CORRECTION ENERGY`

in coupled-cluster.

- DCT TOTAL ENERGY¶
Total energy [Eh] in density cumulant theory. Sum of

`DCT SCF ENERGY`

,`DCT LAMBDA ENERGY`

, and`DCT THREE-PARTICLE ENERGY`

when present.

- DETCI AVG DVEC NORM¶
A measure of configuration interaction convergence.

- DFT FUNCTIONAL TOTAL ENERGY¶
The total electronic energy [Eh] for the underlying functional of the requested DFT method, without any dispersion correction; the first four terms in Eq. (4) or (1). Quantity \(E_{\text{FCTL}}\) in Eqs. (4) and (1). Unless the method includes a dispersion correction, this quantity is equal to

`SCF TOTAL ENERGY`

.

- DFT TOTAL ENERGY¶
The total electronic energy [Eh] for the requested DFT method, \(E_{\text{DFT}}\) in Eq. (1).

\begin{align*} E_{\text{DFT}} & = E_{NN} + E_{1e^-} + E_{2e^-} + E_{xc} + E_{\text{-D}} + E_{\text{DH}} \\ & = E_{\text{FCTL}} + E_{\text{-D}} + E_{\text{DH}} \\ & = E_{\text{SCF}} + E_{\text{DH}} \end{align*}Unless the method is a DFT double-hybrid, this quantity is equal to

`SCF TOTAL ENERGY`

. If the method is neither a double-hybrid, nor dispersion corrected, this quantity is equal to`DFT FUNCTIONAL TOTAL ENERGY`

.

- DFT TOTAL GRADIENT¶
The total electronic gradient [E_h/a0] of the requested DFT method, ({nat}, 3).

- DFT DIPOLE GRADIENT¶
The derivative of the requested DFT method dipole [E_h a0/u] = [(e a0/a0)^2/u] with respect to nuclear perturbations as a degree-of-freedom by dipole component array, (3 * {nat}, 3).

- DFT TOTAL HESSIAN¶
The total electronic second derivative [Eh/a0/a0] for the requested DFT method, (3 * {nat}, 3 * {nat}).

- DFT XC ENERGY¶
The functional energy contribution [Eh] to the total SCF energy (DFT only). Quantity \(E_{xc}\) in Eqs. (4) and (1).

- DFT VV10 ENERGY¶
The VV10 nonlocal contribution [Eh] to the total SCF energy (DFT only). Included in

`DFT FUNCTIONAL TOTAL ENERGY`

.

- DISPERSION CORRECTION ENERGY¶
- fctl DISPERSION CORRECTION ENERGY¶
The dispersion correction [Eh] appended to an underlying functional when a DFT-D method is requested. Quantity \(E_{\text{-D}}\) in Eqs. (4) and (1). When dispersion parameters are untweaked for a functional and dispersion level, labeled QCVariable also defined.

- DOUBLE-HYBRID CORRECTION ENERGY¶
The scaled MP2 correlation energy correction [Eh] appended to an underlying functional when a DH-DFT method is requested. Quantity \(E_{\text{DH}}\) in Eq. (1).

- DMA DISTRIBUTED MULTIPOLES¶
Distributed multipoles in units given by GDMA_MULTIPOLE_UNITS with the row index corresponding to the site and the column index referencing the multipole component. Both indices are zero based, and the Qlm components of the multipoles are ordered as Q00, Q10, Q11c, Q11s, Q20, Q21c, Q21s, Q22c, Q22s, etc.

- DMA TOTAL MULTIPOLES¶
Distributed multipoles as a single row, whose columns are the total multipoles, translated to GDMA_ORIGIN, and summed.

- DMRG-SCF TOTAL ENERGY¶
The total DMRG total electonic energy [Eh]. Not unique because oribital spaces vary.

- DMRG-CASPT2 TOTAL ENERGY¶
The total DMRG plus CASPT2 total electonic energy [Eh] . Not unique because orbital spaces vary.

- EFP DISP ENERGY¶
- EFP ELST ENERGY¶
- EFP EXCH ENERGY¶
- EFP IND ENERGY¶
Respectively, the dispersion, electrostatics, exchange, and induction components of the total electronic interaction energy [Eh] for EFP/EFP computations. The sum of these four components yields

`EFP TOTAL ENERGY`

.

- EFP TOTAL ENERGY¶
The total electronic interaction energy [Eh] for EFP/EFP computations.

- EFP TORQUE¶
The torque, not gradient for EFP/EFP computations.

- ENTHALPY¶
Total enthalpy H [Eh] at given temperature.

- ENTHALPY CORRECTION¶
Sum of electronic, translational, rotational, and vibrational corrections [Eh] to the enthalpy at given temperature.

- ESP AT CENTER n¶
Property of electrostatic potential [Eh / e] at location, usually atom center, n.

- FCI TOTAL ENERGY¶
- FCI CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the full configuration interaction level of theory.

- GIBBS FREE ENERGY¶
Total Gibbs free energy [Eh], free enthalpy at given temperature.

- GIBBS FREE ENERGY CORRECTION¶
Sum of electronic, translational, rotational, and vibrational corrections [Eh] to the free enthalpy at given temperature.

- GRID ELECTRONS TOTAL¶
- GRID ELECTRONS ALPHA¶
- GRID ELECTRONS BETA¶
The number of electrons integrated by the xc quadrature grid.

- HF TOTAL ENERGY¶
The total electronic energy [Eh] for the Hartree–Fock method, without any dispersion correction; the first three (or four, since \(E_{xc} = 0\)) terms in Eq. (4). Quantity \(E_{\text{HF}}\) in Eq. (4).

- HF TOTAL GRADIENT¶
The total electronic gradient [E_h/a0] of the Hartree–Fock method, ({nat}, 3).

- HF DIPOLE GRADIENT¶
The derivative of the Hartree–Fock method dipole [E_h a0/u] = [(e a0/a0)^2/u] with respect to nuclear perturbations as a degree-of-freedom by dipole component array, (3 * {nat}, 3).

- HF TOTAL HESSIAN¶
The total electronic second derivative [Eh/a0/a0] for the Hartree-Fock method, (3 * {nat}, 3 * {nat}).

- LCCD TOTAL ENERGY¶
- LCCD CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the linearized coupled cluster doubles level of theory.

- LCCSD TOTAL ENERGY¶
- LCCSD CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the linearized coupled cluster singles and doubles level of theory.

- LCC2 (+LMP2) TOTAL ENERGY¶
The total electronic energy [Eh] for the local CC2 level of theory.

- LCCSD (+LMP2) TOTAL ENERGY¶
The total electronic energy [Eh] for the local CCSD level of theory.

- LOWDIN CHARGES¶
Property of partial atomic charges [e] by the method of Löwdin, (nat,).

- MAYER INDICES¶
Property of Mayer bond indices, (nat, nat).

- MBIS CHARGES¶
- MBIS DIPOLES¶
- MBIS OCTUPOLES¶
- MBIS QUADRUPOLES¶
Per-atom charges [e], dipoles [e a0], quadrupoles [e a0^2], and octupoles [e a0^3] resulting from partitioning the total electron density through the Minimal Basis Iterative Stockholder (MBIS) Charge Partitioning Scheme.

- MBIS FREE ATOM n VOLUME¶
Free-atom volume [a0^3] for atom n, computed using the MBIS charge partitioning scheme. Free atom densities are computed at the same level of theory as the parent MBIS calculation, with UHF turned on as needed.

- MBIS RADIAL MOMENTS <R^3>¶
Per-atom expectation value of r^3 [a0^3], equivalent to the volume of the MBIS-partitioned density.

- MBIS VALENCE WIDTHS¶
Per-atom density width [a0] of the associated valence charge computed from an MBIS partitioned density. Equivalent to the inverse of the linear decay rate of the atomic density.

- MBIS VOLUME RATIOS¶
Per-atom ratio between the atomic volume (<R^3>) and the free-atomic volume, unitless.

- MCSCF TOTAL ENERGY¶
Multiconfigurational self-consistent-field energy [Eh] in the course of a configuration interaction computation. May be single-root or state-averaged.

- mtd DIPOLE¶
Dipole array [e a0] for the named method, (3,).

- mtd DIPOLE X¶
- mtd DIPOLE Y¶
- mtd DIPOLE Z¶
The three components of the named method dipole [Debye]. Deprecated in favor of

`mtd DIPOLE`

.

- mtd QUADRUPOLE¶
Redundant quadrupole array [e a0^2] for the named method, (3, 3).

- mtd QUADRUPOLE XX¶
- mtd QUADRUPOLE XY¶
- mtd QUADRUPOLE XZ¶
- mtd QUADRUPOLE YY¶
- mtd QUADRUPOLE YZ¶
- mtd QUADRUPOLE ZZ¶
The six components of the named method quadrupole [Debye Ang]. Deprecated in favor of

`mtd QUADRUPOLE`

.

- mtd OCTUPOLE¶
Redundant octupole array [e a0^3] for the named method, (3, 3, 3).

- mtd OCTUPOLE XXX¶
- mtd OCTUPOLE XXY¶
- mtd OCTUPOLE XXZ¶
- mtd OCTUPOLE XYY¶
- mtd OCTUPOLE XYZ¶
- mtd OCTUPOLE XZZ¶
- mtd OCTUPOLE YYY¶
- mtd OCTUPOLE YYZ¶
- mtd OCTUPOLE YZZ¶
- mtd OCTUPOLE ZZZ¶
The ten components of the named method octupole [Debye Ang^2]. Deprecated in favor of

`mtd OCTUPOLE`

.

- mtd HEXADECAPOLE¶
Redundant hexadecapole array [e a0^4] for the named method, (3, 3, 3, 3).

- mtd HEXADECAPOLE XXXX¶
- mtd HEXADECAPOLE XXXY¶
- mtd HEXADECAPOLE ZZZZ¶
The 15 components of the named method hexadecapole [Debye Ang^3]. Deprecated in favor of

`mtd HEXADECAPOLE`

.

- mtd 32-POLE¶
Redundant 32-pole array [e a0^5] for the named method, (3, 3, 3, 3, 3).

- mtd 32-POLE XXXXX¶
- mtd 32-POLE XXXXY¶
- mtd 32-POLE ZZZZZ¶
The 21 components of the named method 32-pole [Debye Ang^4]. Deprecated in favor of

`mtd 32-POLE`

.

- mtd 64-POLE¶
Redundant 64-pole array [e a0^6] for the named method, (3, 3, 3, 3, 3, 3).

- mtd 64-POLE XXXXXX¶
- mtd 64-POLE XXXXXY¶
- mtd 64-POLE ZZZZZZ¶
The 28 components of the named method 64-pole [Debye Ang^5]. Deprecated in favor of

`mtd 64-POLE`

.

- mtd 128-POLE¶
Redundant 128-pole array [e a0^7] for the named method, (3, 3, 3, 3, 3, 3, 3).

- mtd 128-POLE XXXXXXX¶
- mtd 128-POLE XXXXXXY¶
- mtd 128-POLE ZZZZZZZ¶
The 36 components of the named method 128-pole [Debye Ang^6]. Deprecated in favor of

`mtd 128-POLE`

.

- MP2 TOTAL ENERGY¶
- MP2 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the MP2 level of theory.

- MP2 DIPOLE GRADIENT¶
The derivative of the MP2 level of theory dipole [E_h a0/u] = [(e a0/a0)^2/u] with respect to nuclear perturbations as a degree-of-freedom by dipole component array, (3 * {nat}, 3).

- MP2 TOTAL HESSIAN¶
The total electronic second derivative [Eh/a0/a0] for the MP2 level of theory, (3 * {nat}, 3 * {nat}).

- MP2.5 TOTAL ENERGY¶
- MP2.5 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the MP2.5 level of theory.

- MP3 TOTAL ENERGY¶
- MP3 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the MP3 level of theory.

- MP4(T) CORRECTION ENERGY¶
The MP4 triples component [Eh]. Quantity is second right-hand term in Eq. (2).

- MP4(SDQ) TOTAL ENERGY¶
- MP4(SDQ) CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the MP4 singles, doubles, quadruples level of theory. Quantity

`MP4(SDQ) CORRELATION ENERGY`

is first right-hand term in Eq. (2).

- MP4 TOTAL ENERGY¶
- MP4 CORRELATION ENERGY¶
- MP4(SDTQ) TOTAL ENERGY¶
- MP4(SDTQ) CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the full MP4 level of theory. Quantity

`MP4 CORRELATION ENERGY`

/`MP4(SDTQ) CORRELATION ENERGY`

is left-hand term in Eq. (2).(2)¶\[E_{\text{MP4}} = E_{\text{MP4(SDQ)}} + E_{\text{MP4(T)}}\]

- MPn TOTAL ENERGY¶
- MPn CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the labeled Møller–Plesset perturbation theory level.

*n*is MP perturbation order.

- MP2 DOUBLES ENERGY¶
- MP2.5 DOUBLES ENERGY¶
- MP3 DOUBLES ENERGY¶
- CEPA(0) DOUBLES ENERGY¶
- CEPA(1) DOUBLES ENERGY¶
- CEPA(2) DOUBLES ENERGY¶
- CEPA(3) DOUBLES ENERGY¶
- CISD DOUBLES ENERGY¶
- QCISD DOUBLES ENERGY¶
- LCCD DOUBLES ENERGY¶
- CCD DOUBLES ENERGY¶
- LCCSD DOUBLES ENERGY¶
- CCSD DOUBLES ENERGY¶
- OMP2 DOUBLES ENERGY¶
- OMP2.5 DOUBLES ENERGY¶
- OMP3 DOUBLES ENERGY¶
- OLCCD DOUBLES ENERGY¶
The doubles portion [Eh] of the named correlation energy including same-spin and opposite-spin correlations.

- MP2 SINGLES ENERGY¶
- MP2.5 SINGLES ENERGY¶
- MP3 SINGLES ENERGY¶
- CEPA(0) SINGLES ENERGY¶
- CEPA(1) SINGLES ENERGY¶
- CEPA(2) SINGLES ENERGY¶
- CEPA(3) SINGLES ENERGY¶
- CISD SINGLES ENERGY¶
- QCISD SINGLES ENERGY¶
- LCCD SINGLES ENERGY¶
- CCD SINGLES ENERGY¶
- LCCSD SINGLES ENERGY¶
- CCSD SINGLES ENERGY¶
- OLCCD SINGLES ENERGY¶
The singles portion [Eh] of the named correlation energy. Zero except in ROHF.

- MP2 SAME-SPIN CORRELATION ENERGY¶
- MP2.5 SAME-SPIN CORRELATION ENERGY¶
- MP3 SAME-SPIN CORRELATION ENERGY¶
- CEPA(0) SAME-SPIN CORRELATION ENERGY¶
- CEPA(1) SAME-SPIN CORRELATION ENERGY¶
- CEPA(2) SAME-SPIN CORRELATION ENERGY¶
- CEPA(3) SAME-SPIN CORRELATION ENERGY¶
- CISD SAME-SPIN CORRELATION ENERGY¶
- QCISD SAME-SPIN CORRELATION ENERGY¶
- ACPF SAME-SPIN CORRELATION ENERGY¶
- AQCC SAME-SPIN CORRELATION ENERGY¶
- LCCD SAME-SPIN CORRELATION ENERGY¶
- CCD SAME-SPIN CORRELATION ENERGY¶
- LCCSD SAME-SPIN CORRELATION ENERGY¶
- CCSD SAME-SPIN CORRELATION ENERGY¶
- OLCCD SAME-SPIN CORRELATION ENERGY¶
The unscaled portion [Eh] of the named correlation energy from same-spin or triplet doubles correlations.

- MP2 OPPOSITE-SPIN CORRELATION ENERGY¶
- MP2.5 OPPOSITE-SPIN CORRELATION ENERGY¶
- MP3 OPPOSITE-SPIN CORRELATION ENERGY¶
- CEPA(0) OPPOSITE-SPIN CORRELATION ENERGY¶
- CEPA(1) OPPOSITE-SPIN CORRELATION ENERGY¶
- CEPA(2) OPPOSITE-SPIN CORRELATION ENERGY¶
- CEPA(3) OPPOSITE-SPIN CORRELATION ENERGY¶
- CISD OPPOSITE-SPIN CORRELATION ENERGY¶
- QCISD OPPOSITE-SPIN CORRELATION ENERGY¶
- ACPF OPPOSITE-SPIN CORRELATION ENERGY¶
- AQCC OPPOSITE-SPIN CORRELATION ENERGY¶
- LCCD OPPOSITE-SPIN CORRELATION ENERGY¶
- CCD OPPOSITE-SPIN CORRELATION ENERGY¶
- LCCSD OPPOSITE-SPIN CORRELATION ENERGY¶
- CCSD OPPOSITE-SPIN CORRELATION ENERGY¶
- OLCCD OPPOSITE-SPIN CORRELATION ENERGY¶
The unscaled portion [Eh] of the named correlation energy from opposite-spin or singlet doubles correlations.

- MRPT TOTAL ENERGY¶
- MP2-CCSD TOTAL ENERGY¶
- MRCC TOTAL ENERGY¶
Energies [Eh] from correlated multi-reference theories.

- MULLIKEN CHARGES¶
Property of partial atomic charges [e] by the method of Mulliken, (nat,).

- NAUX (SCF)¶
- NAUX (CC)¶
Convenience storage of number of functions [] in the auxiliary basis set for named stage of the calculation.

- NBODY (i, j, ..., k)@(a, b, ..., c) TOTAL ENERGY¶
The total energy [Eh] of a component of the requested N-Body energy. The first parenthetical list over

*i*,*j*, …,*k*enumerates molecular fragments included in the computation in 1-indexed, input-file order, while the second enumerates list over*a*,*b*, …,*c*enumerates which fragments contribute basis functions to the computation. For example,`(1, 2)@(1, 2, 3, 4)`

indicates that the fragments 1 and 2 are explicitly included in the energy computation, with basis functions from each of fragments 1, 2, 3, & 4 included in the basis set. Therefore, the basis functions from fragments 3 and 4 are included as ghost functions within the energy computation.

- NUCLEAR REPULSION ENERGY¶
The nuclear repulsion energy contribution [Eh] to the total SCF energy. Quantity \(E_{NN}\) in Eq. (4).

(3)¶\[E_{NN} = \sum_{i, j<i}^{N_{atom}}\frac{Z_i Z_j}{|\mathbf{R}_i - \mathbf{R}_j|}\]

- OCEPA(0) TOTAL ENERGY¶
- OCEPA(0) CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the orbital-optimized CEPA(0) level of theory.

- OLCCD TOTAL ENERGY¶
- OLCCD CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the orbital-optimized linearized coupled cluster doubles level of theory.

- OLCCD REFERENCE CORRECTION ENERGY¶
The additional correction to the SCF reference energy [Eh] for the orbital-optimized linearized coupled cluster doubles level of theory.

- OMP2 TOTAL ENERGY¶
- OMP2 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the orbital-optimized MP2 level of theory.

- OMP2.5 TOTAL ENERGY¶
- OMP2.5 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the orbital-optimized MP2.5 level of theory.

- OMP3 TOTAL ENERGY¶
- OMP3 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the orbital-optimized MP3 level of theory.

- ONE-ELECTRON ENERGY¶
The one-electron energy contribution [Eh] to the total SCF energy. Quantity \(E_{1e^-}\) in Eq. (4).

- PCM POLARIZATION ENERGY¶
The energy contribution [Eh] from the polarizable continuum model for solvation.

- PE ENERGY¶
The energy contribution [Eh] from the polarizable embedding model for solvation.

- QCISD TOTAL ENERGY¶
- QCISD CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the quadratic configuration interaction singles and doubles level of theory.

- QCISD(T) TOTAL ENERGY¶
- QCISD(T) CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the quadratic configuration interaction singles and doubles with perturbative triples correction level of theory.

- SAPT DISP ENERGY¶
- SAPT ELST ENERGY¶
- SAPT EXCH ENERGY¶
- SAPT IND ENERGY¶
Respectively, the dispersion, electrostatics, exchange, and induction components of the total electronic interaction energy [Eh] for the requested SAPT level of theory. The sum of these four components yields

`SAPT TOTAL ENERGY`

.

- SAPT TOTAL ENERGY¶
- SAPT ENERGY¶
The total electronic interaction energy [Eh] for the requested SAPT level of theory.

- SAPT ELST10,R ENERGY¶
An electrostatics-classified SAPT term energy [Eh] implemented for SAPT0.

- SAPT ELST EXTERN-EXTERN ENERGY¶
Electrostatic interaction [Eh] between the point charges in fragments A and B in F/I-SAPT.

- SAPT EXCH10 ENERGY¶
An exchange-classified SAPT term energy [Eh] implemented for SAPT0.

- SAPT EXCH10(S^2) ENERGY¶
An exchange-classified SAPT term energy [Eh] implemented for SAPT0.

- SAPT IND20,R ENERGY¶
- SAPT EXCH-IND20,R ENERGY¶
- SAPT IND20,U ENERGY¶
- SAPT EXCH-IND20,U ENERGY¶
An induction-classified SAPT term energy [Eh] implemented for SAPT0.

- SAPT DISP20 ENERGY¶
- SAPT EXCH-DISP20 ENERGY¶
A dispersion-classified SAPT term energy [Eh] implemented for SAPT0.

- SAPT EXCH-DISP20(S^INF) ENERGY¶
A dispersion-classified SAPT term energy [Eh] implemented for SAPT0. See Second-Order Exchange Terms without Single-Exchange Approximation.

- SAPT SAME-SPIN DISP20 ENERGY¶
- SAPT SAME-SPIN EXCH-DISP20 ENERGY¶
The portion of

`SAPT DISP20 ENERGY`

or`SAPT EXCH-DISP20 ENERGY`

resulting from from same-spin or triplet doubles correlations.

- SAPT HF(2) ENERGY ABC(HF)¶
The total Hartree–Fock energy [Eh] of the supersystem implemented for F/I-SAPT.

- SAPT HF(2) ENERGY AC(0)¶
The Hartree–Fock energy [Eh] of subsystems A and C implemented for F/I-SAPT.

- SAPT HF(2) ENERGY BC(0)¶
The Hartree–Fock energy [Eh] of subsystems B and C implemented for F/I-SAPT.

- SAPT HF(2) ENERGY A(0)¶
The Hartree–Fock energy [Eh] of subsystem A implemented for F/I-SAPT.

- SAPT HF(2) ENERGY B(0)¶
The Hartree–Fock energy [Eh] of subsystem B implemented for F/I-SAPT.

- SAPT HF(2) ENERGY AC(HF)¶
The Hartree–Fock localized energy [Eh] of subsystems A and C implemented for F/I-SAPT.

- SAPT HF(2) ENERGY BC(HF)¶
The Hartree–Fock localized energy [Eh] of subsystems B and C implemented for F/I-SAPT.

- SAPT HF(2) ENERGY AB(HF)¶
The Hartree–Fock localized energy [Eh] of subsystems A and B implemented for F/I-SAPT.

- SAPT HF(2) ENERGY A(HF)¶
The Hartree–Fock localized energy [Eh] of subsystem A implemented for F/I-SAPT.

- SAPT HF(2) ENERGY B(HF)¶
The Hartree–Fock localized energy [Eh] of subsystem B implemented for F/I-SAPT.

- SAPT HF(2) ENERGY C¶
The Hartree–Fock energy [Eh] of subsystem C implemented for F/I-SAPT.

- SAPT HF(2) ENERGY HF¶
The FI-SAPT Hartree–Fock interaction energy [Eh] implemented for F/I-SAPT.

- SAPT ELST12,R ENERGY¶
An electrostatics-classified SAPT term energy [Eh] implemented for SAPT2.

- SAPT EXCH11(S^2) ENERGY¶
- SAPT EXCH12(S^2) ENERGY¶
An exchange-classified SAPT term energy [Eh] implemented for SAPT2.

- SAPT IND22 ENERGY¶
- SAPT EXCH-IND22 ENERGY¶
An induction-classified SAPT term energy [Eh] implemented for SAPT2.

- SAPT DISP21 ENERGY¶
A dispersion-classified SAPT term energy [Eh] implemented for SAPT2+.

- SAPT DISP22(SDQ) ENERGY¶
- SAPT DISP22(T) ENERGY¶
- SAPT EST.DISP22(T) ENERGY¶
Dispersion-classified MBPT-based SAPT term energy [Eh] implemented for SAPT2+.

- SAPT DISP2(CCD) ENERGY¶
- SAPT DISP22(S)(CCD) ENERGY¶
- SAPT DISP22(T)(CCD) ENERGY¶
- SAPT EST.DISP22(T)(CCD) ENERGY¶
Dispersion-classified coupled-cluster-based SAPT term energy [Eh] implemented for SAPT2+.

- SAPT ELST13,R ENERGY¶
An electrostatics-classified SAPT term energy [Eh] implemented for SAPT2+(3).

- SAPT IND30,R ENERGY¶
- SAPT IND-DISP30 ENERGY¶
- SAPT EXCH-IND30,R ENERGY¶
A induction-classified SAPT term energy [Eh] implemented for SAPT2+3.

- SAPT DISP30 ENERGY¶
- SAPT EXCH-DISP30 ENERGY¶
- SAPT EXCH-IND-DISP30 ENERGY¶
A dispersion-classified SAPT term energy [Eh] implemented for SAPT2+3.

- SAPT ALPHA¶
SAPT exchange-scaling alpha.

- SAPT CT ENERGY¶
SAPT charge-transfer energy.

- SAPT HF TOTAL ENERGY¶
An induction-classified correction from HF implemented for SAPT0. Value varies by SAPT level.

- SAPT MP2 CORRELATION ENERGY¶
An induction-classified correction from MP2 implemented for SAPT2. Value varies by SAPT level.

- SAPT0 DISP ENERGY¶
- SAPT0 ELST ENERGY¶
- SAPT0 EXCH ENERGY¶
- SAPT0 IND ENERGY¶
- SSAPT0 DISP ENERGY¶
- SSAPT0 ELST ENERGY¶
- SSAPT0 EXCH ENERGY¶
- SSAPT0 IND ENERGY¶
- SAPT2 DISP ENERGY¶
- SAPT2 ELST ENERGY¶
- SAPT2 EXCH ENERGY¶
- SAPT2 IND ENERGY¶
- SAPT2+ DISP ENERGY¶
- SAPT2+ ELST ENERGY¶
- SAPT2+ EXCH ENERGY¶
- SAPT2+ IND ENERGY¶
- SAPT2+(3) DISP ENERGY¶
- SAPT2+(3) ELST ENERGY¶
- SAPT2+(3) EXCH ENERGY¶
- SAPT2+(3) IND ENERGY¶
- SAPT2+3 DISP ENERGY¶
- SAPT2+3 ELST ENERGY¶
- SAPT2+3 EXCH ENERGY¶
- SAPT2+3 IND ENERGY¶
Respectively, the dispersion, electrostatics, exchange, and induction components of the total electronic interaction energy [Eh] for the given SAPT level of theory. The sum of these four components yields the

*SAPT Level*TOTAL ENERGY

- SAPT0 TOTAL ENERGY¶
- SSAPT0 TOTAL ENERGY¶
- SAPT2 TOTAL ENERGY¶
- SAPT2+ TOTAL ENERGY¶
- SAPT2+(3) TOTAL ENERGY¶
- SAPT2+3 TOTAL ENERGY¶
The total electronic interaction energy [Eh] for the labeled SAPT level of theory.

- SAPT2+(CCD) DISP ENERGY¶
- SAPT2+(CCD) ELST ENERGY¶
- SAPT2+(CCD) EXCH ENERGY¶
- SAPT2+(CCD) IND ENERGY¶
- SAPT2+(3)(CCD) DISP ENERGY¶
- SAPT2+(3)(CCD) ELST ENERGY¶
- SAPT2+(3)(CCD) EXCH ENERGY¶
- SAPT2+(3)(CCD) IND ENERGY¶
- SAPT2+3(CCD) DISP ENERGY¶
- SAPT2+3(CCD) ELST ENERGY¶
- SAPT2+3(CCD) EXCH ENERGY¶
- SAPT2+3(CCD) IND ENERGY¶
Respectively, the dispersion, electrostatics, exchange, and induction components of the total electronic interaction energy [Eh] for the given SAPT level of theory that incorporates coupled-cluster dispersion. The sum of these four components yields the

*SAPT Level*TOTAL ENERGY

- SAPT2+(CCD) TOTAL ENERGY¶
- SAPT2+(3)(CCD) TOTAL ENERGY¶
- SAPT2+3(CCD) TOTAL ENERGY¶
The total electronic interaction energy [Eh] for the labeled SAPT level of theory that incorporates coupled-cluster dispersion.

- SAPT2+DMP2 DISP ENERGY¶
- SAPT2+DMP2 ELST ENERGY¶
- SAPT2+DMP2 EXCH ENERGY¶
- SAPT2+DMP2 IND ENERGY¶
- SAPT2+(3)DMP2 DISP ENERGY¶
- SAPT2+(3)DMP2 ELST ENERGY¶
- SAPT2+(3)DMP2 EXCH ENERGY¶
- SAPT2+(3)DMP2 IND ENERGY¶
- SAPT2+3DMP2 DISP ENERGY¶
- SAPT2+3DMP2 ELST ENERGY¶
- SAPT2+3DMP2 EXCH ENERGY¶
- SAPT2+3DMP2 IND ENERGY¶
- SAPT2+(CCD)DMP2 DISP ENERGY¶
- SAPT2+(CCD)DMP2 ELST ENERGY¶
- SAPT2+(CCD)DMP2 EXCH ENERGY¶
- SAPT2+(CCD)DMP2 IND ENERGY¶
- SAPT2+(3)(CCD)DMP2 DISP ENERGY¶
- SAPT2+(3)(CCD)DMP2 ELST ENERGY¶
- SAPT2+(3)(CCD)DMP2 EXCH ENERGY¶
- SAPT2+(3)(CCD)DMP2 IND ENERGY¶
- SAPT2+3(CCD)DMP2 DISP ENERGY¶
- SAPT2+3(CCD)DMP2 ELST ENERGY¶
- SAPT2+3(CCD)DMP2 EXCH ENERGY¶
- SAPT2+3(CCD)DMP2 IND ENERGY¶
Respectively, the dispersion, electrostatics, exchange, and induction components of the total electronic interaction energy [Eh] for the given SAPT level of theory that incorporates MP2 induction correction. The sum of these four components yields the

*SAPT Level*TOTAL ENERGY

- SAPT2+DMP2 TOTAL ENERGY¶
- SAPT2+(3)DMP2 TOTAL ENERGY¶
- SAPT2+3DMP2 TOTAL ENERGY¶
- SAPT2+(CCD)DMP2 TOTAL ENERGY¶
- SAPT2+(3)(CCD)DMP2 TOTAL ENERGY¶
- SAPT2+3(CCD)DMP2 TOTAL ENERGY¶
The total electronic interaction energy [Eh] for the labeled SAPT level of theory that incorporates MP2 induction correction.

- SCF ITERATIONS¶
- ADC ITERATIONS¶
- CCSD ITERATIONS¶
- OPTIMIZATION ITERATIONS¶
Number of iterations [] in the named iterative method or optimization procedure.

- SCF DIPOLE¶
Dipole array [e a0] for the SCF stage, (3,).

- SCF DIPOLE X¶
- SCF DIPOLE Y¶
- SCF DIPOLE Z¶
The three components of the SCF dipole [Debye]. Deprecated in favor of

`SCF DIPOLE`

.

- SCF QUADRUPOLE¶
Redundant quadrupole array [e a0^2] for the SCF stage, (3, 3).

- SCF QUADRUPOLE XX¶
- SCF QUADRUPOLE XY¶
- SCF QUADRUPOLE XZ¶
- SCF QUADRUPOLE YY¶
- SCF QUADRUPOLE YZ¶
- SCF QUADRUPOLE ZZ¶
The six components of the SCF quadrupole [Debye Ang]. Deprecated in favor of

`SCF QUADRUPOLE`

.

- SCF TOTAL ENERGY¶
The total electronic energy [Eh] of the SCF stage of the calculation. The

variables from subsequent stages of a calculation are often the corresponding*method*CORRELATION ENERGY

variables less this quantity. Constructed from Eq. (4), where this quantity is \(E_{\text{SCF}}\).*method*TOTAL ENERGY\begin{align*} E_{\text{SCF}} & = E_{NN} + E_{1e^-} + E_{2e^-} + E_{xc} + E_{\text{-D}} \\ & = E_{\text{FCTL/HF}} + E_{\text{-D}} \end{align*}Unless the method includes a dispersion correction, this quantity is equal to

`HF TOTAL ENERGY`

(for HF) or`DFT FUNCTIONAL TOTAL ENERGY`

(for DFT). Unless the method is a DFT double-hybrid, this quantity is equal to`DFT TOTAL ENERGY`

.

- SCF TOTAL GRADIENT¶
The total electronic gradient [E_h/a0] of the SCF stage of the calculation, ({nat}, 3).

- SCF DIPOLE GRADIENT¶
The derivative of the SCF stage dipole [E_h a0/u] = [(e a0/a0)^2/u] with respect to nuclear perturbations as a degree-of-freedom by dipole component array, (3 * {nat}, 3).

- SCF TOTAL HESSIAN¶
The total electronic second derivative [Eh/a0/a0] for the SCF stage, (3 * {nat}, 3 * {nat}).

- SCF STABILITY EIGENVALUES¶
Array of eigenvalues from UHF or ROHF stability analysis.

- SCS-CCSD TOTAL ENERGY¶
- SCS-CCSD CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the CCSD-like method formed by reweighting

`CCSD DOUBLES ENERGY`

by 1.27 opposite-spin and 1.13 same-spin contributions, with any singles carried along.

- SCS-MP2 TOTAL ENERGY¶
- SCS-MP2 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the MP2-like method formed by reweighting

`MP2 DOUBLES ENERGY`

by 6/5 opposite-spin and 1/3 same-spin contributions, with any singles carried along.

- SCS-MP2-VDW TOTAL ENERGY¶
- SCS-MP2-VDW CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the MP2-like method formed by reweighting

`MP2 DOUBLES ENERGY`

by 1.28 opposite-spin and 0.50 same-spin contributions, with any singles carried along. DOI: 10.1080/00268970802641242

- SCS(N)-MP2 TOTAL ENERGY¶
- SCS(N)-MP2 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the MP2-like method formed by reweighting

`MP2 DOUBLES ENERGY`

by 0 opposite-spin and 1.76 same-spin contributions, with any singles carried along. doi: 10.1021/ct6002737

- SCS(N)-OMP2 CORRELATION ENERGY¶
- SCS(N)-OMP2 TOTAL ENERGY¶
- SCSN-OMP2 CORRELATION ENERGY¶
- SCSN-OMP2 TOTAL ENERGY¶
Two spellings of a discontinued QCVariable that may still appear because the code is frozen pending an update.

- SCS-OMP2 TOTAL ENERGY¶
- SCS-OMP2 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the OMP2-like method formed by reweighting

`OMP2 DOUBLES ENERGY`

by 6/5 opposite-spin and 1/3 same-spin contributions, with any singles carried along.

- SCS-MP3 TOTAL ENERGY¶
- SCS-MP3 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the MP3-like method formed by reweighting the difference between

`MP3 DOUBLES ENERGY`

and`MP2 DOUBLES ENERGY`

by 0.25, atop the SCS-MP2 energy, with any singles carried along.

- SCS-OMP3 TOTAL ENERGY¶
- SCS-OMP3 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the OMP3-like method formed by reweighting the difference between

`OMP3 DOUBLES ENERGY`

and`OMP2 DOUBLES ENERGY`

by 0.25, atop the SCS-OMP2 energy, with any singles carried along.

- SOS-MP2 TOTAL ENERGY¶
- SOS-MP2 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the MP2-like method formed by reweighting

`MP2 DOUBLES ENERGY`

by 1.3 opposite-spin and 0 same-spin contributions, with any singles carried along.

- SOS-OMP2 TOTAL ENERGY¶
- SOS-OMP2 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the OMP2-like method formed by reweighting

`OMP2 DOUBLES ENERGY`

by 1.2 opposite-spin and 0 same-spin contributions, with any singles carried along.

- SOS-OMP3 TOTAL ENERGY¶
- SOS-OMP3 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the OMP3-like method formed by reweighting the difference between

`OMP3 DOUBLES ENERGY`

and`OMP2 DOUBLES ENERGY`

by 0.25, atop the SOS-OMP2 energy using non-canonical weighting, with any singles carried along.

- SOS-PI-MP2 TOTAL ENERGY¶
- SOS-PI-MP2 CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the MP2-like method formed by reweighting

`MP2 DOUBLES ENERGY`

by 1.4 opposite-spin and 0 same-spin contributions, with any singles carried along.

- TDDFT ROOT 0 -> ROOT m EXCITATION ENERGY - h SYMMETRY¶
- TD-fctl ROOT 0 -> ROOT m EXCITATION ENERGY - h SYMMETRY¶
- ADC ROOT 0 -> ROOT m EXCITATION ENERGY - h SYMMETRY¶
- EOM-CCSD ROOT 0 -> ROOT m EXCITATION ENERGY - h SYMMETRY¶
The excitation energy of given method from ground state to root m in h symmetry (if available). DFT functional labeled if canonical.

- TDDFT ROOT n TOTAL ENERGY - h SYMMETRY¶
- TD-fctl ROOT n TOTAL ENERGY - h SYMMETRY¶
- ADC ROOT n TOTAL ENERGY - h SYMMETRY¶
- EOM-CCSD ROOT n TOTAL ENERGY - h SYMMETRY¶
The total energy of given method from ground state to root m in h symmetry.

- ADC ROOT 0 -> ROOT m CORRELATION ENERGY - h SYMMETRY¶
- EOM-CCSD ROOT 0 -> ROOT m CORRELATION ENERGY - h SYMMETRY¶
The correlation energy of given method from ground state reference energy to root m in h symmetry.

- TD-fctl ROOT 0 -> ROOT m OSCILLATOR STRENGTH (LEN) - h SYMMETRY¶
- TD-fctl ROOT 0 -> ROOT m OSCILLATOR STRENGTH (VEL) - h SYMMETRY¶
The oscillator strength in length or velocity gauge of named method from ground state to root m in h symmetry (if available). DFT functional labeled if canonical.

- TD-fctl ROOT 0 -> ROOT m ROTATORY STRENGTH (LEN) - h SYMMETRY¶
- TD-fctl ROOT 0 -> ROOT m ROTATORY STRENGTH (VEL) - h SYMMETRY¶
The rotatory strength in length or velocity gauge of named method from ground state to root m in h symmetry (if available). DFT functional labeled if canonical.

- THERMAL ENERGY¶
Total thermal energy E [Eh] at given temperature.

- THERMAL ENERGY CORRECTION¶
Sum of electronic, translational, rotational, and vibrational corrections [Eh] to the thermal energy at given temperature.

- TWO-ELECTRON ENERGY¶
The two-electron energy contribution [Eh] to the total SCF energy. Quantity \(E_{2e^-}\) in Eq. (4).

- UNCP-CORRECTED 2-BODY INTERACTION ENERGY¶
The interaction energy [Eh] considering only two-body interactions, computed without counterpoise correction. Related variable

`CP-CORRECTED 2-BODY INTERACTION ENERGY`

.\[E_{\text{IE}} = E_{dimer} - \sum_{monomer}^{n}{E_{monomer}^{\text{unCP}}}\]

- WIBERG LOWDIN INDICES¶
Property of Wiberg bond indices using orthogonal Löwdin orbitals, (nat, nat).

- ZAPTn TOTAL ENERGY¶
- ZAPTn CORRELATION ENERGY¶
The total electronic energy [Eh] and correlation energy component [Eh] for the labeled Z-averaged perturbation theory level.

*n*is ZAPT perturbation order.

- ZERO K ENTHALPY¶
Total electronic and zero-point energy [Eh] at 0 [K].

- ZPVE¶
Vibrational zero-point energy [Eh] at 0 [K].