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CCLAMBDA

Solves for the Lagrange multipliers, which are needed whenever coupled cluster properties or gradients are requested.

General

ABCD

Type of ABCD algorithm will be used

  • Type: string
  • Default: NEW

AO_BASIS

The algorithm to use for the \left<VV||VV\right> terms

  • Type: string
  • Possible Values: NONE, DISK, DIRECT
  • Default: NONE

CACHELEVEL

Cacheing level for libdpd governing the storage of amplitudes, integrals, and intermediates in the CC procedure. A value of 0 retains no quantities in cache, while a level of 6 attempts to store all quantities in cache. For particularly large calculations, a value of 0 may help with certain types of memory problems. The default is 2, which means that all four-index quantites with up to two virtual-orbital indices (e.g., \langle ij | ab \rangle> integrals) may be held in the cache.

  • Type: integer
  • Default: 2

DIIS

Do use DIIS extrapolation to accelerate convergence?

LOCAL

Do simulate the effects of local correlation techniques?

LOCAL_CPHF_CUTOFF

Cutoff value for local-coupled-perturbed-Hartree-Fock

  • Type: double
  • Default: 0.10

LOCAL_CUTOFF

Value (always between one and zero) for the Broughton-Pulay completeness check used to contruct orbital domains for local-CC calculations. See J. Broughton and P. Pulay, J. Comp. Chem. 14, 736-740 (1993) and C. Hampel and H.-J. Werner, J. Chem. Phys. 104, 6286-6297 (1996).

  • Type: double
  • Default: 0.02

LOCAL_FILTER_SINGLES

Do apply local filtering to single de-excitation (\lambda 1 amplitudes?

LOCAL_METHOD

Type of local-CCSD scheme to be simulated. WERNER (unique avaliable option) selects the method developed by H.-J. Werner and co-workers.

  • Type: string
  • Default: WERNER

LOCAL_PAIRDEF

Definition of local pair domains

  • Type: string
  • Default: No Default

LOCAL_WEAKP

Desired treatment of “weak pairs” in the local-CCSD method. The value of NONE (unique avaliable option) treats weak pairs in the same manner as strong pairs.

  • Type: string
  • Default: NONE

MAXITER

Maximum number of iterations

  • Type: integer
  • Default: 50

NUM_AMPS_PRINT

Number of important CC amplitudes per excitation level to print. CC analog to NUM_DETS_PRINT

  • Type: integer
  • Default: 10

PROP_ALL

Compute unrelaxed properties for all excited states.

PROP_ROOT

Root number (within its irrep) for computing properties

  • Type: integer
  • Default: 1

PROP_SYM

The symmetry of states

  • Type: integer
  • Default: 1

RESTART

Do restart the coupled-cluster iterations from old \lambda_1 and \lambda_2 amplitudes?

ROOTS_PER_IRREP

The number of electronic states to computed, per irreducible representation

  • Type: array
  • Default: No Default

R_CONVERGENCE

Convergence criterion for wavefunction (change) in CC lambda-amplitude equations.

SEKINO

Do Sekino-Bartlett size-extensive model-III?

ZETA

Do use zeta?

Expert

JOBTYPE

Type of job being performed

  • Type: string
  • Default: No Default

WFN

Wavefunction type

  • Type: string
  • Default: SCF