CCENERGY¶
Computes coupled cluster energies. Called as part of any coupled cluster computation.
General¶
BRUECKNER_ORBS_R_CONVERGENCE¶
Convergence criterion for Breuckner orbitals. The convergence is determined based on the largest
amplitude. Default adjusts depending on E_CONVERGENCE
- Type: conv double
- Default: 1e-5
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.,
integrals) may be held in the cache.
- Type: integer
- Default: 2
CACHETYPE¶
Selects the priority type for maintaining the automatic memory cache used by the libdpd codes. A value of LOW selects a “low priority” scheme in which the deletion of items from the cache is based on pre-programmed priorities. A value of LRU selects a “least recently used” scheme in which the oldest item in the cache will be the first one deleted.
- Type: string
- Possible Values: LOW, LRU
- Default: LOW
CC_NUM_THREADS¶
Number of threads
- Type: integer
- Default: 1
CC_OS_SCALE¶
Coupled-cluster opposite-spin scaling value
- Type: double
- Default: 1.27
CC_SS_SCALE¶
Coupled-cluster same-spin scaling value
- Type: double
- Default: 1.13
E_CONVERGENCE¶
Convergence criterion for energy. See Table Post-SCF Convergence for default convergence criteria for different calculation types.
- Type: conv double
- Default: 1e-8
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_METHOD¶
Type of local-CCSD scheme to be simulated. WERNER selects the method developed by H.-J. Werner and co-workers, and AOBASIS selects the method developed by G.E. Scuseria and co-workers (currently inoperative).
- Type: string
- Possible Values: WERNER, AOBASIS
- Default: WERNER
LOCAL_PAIRDEF¶
Definition of local pair domains, default is BP, Boughton-Pulay.
- Type: string
- Possible Values: BP, RESPONSE
- Default: BP
LOCAL_WEAKP¶
Desired treatment of “weak pairs” in the local-CCSD method. A value of NEGLECT ignores weak pairs entirely. A value of NONE treats weak pairs in the same manner as strong pairs. A value of MP2 uses second-order perturbation theory to correct the local-CCSD energy computed with weak pairs ignored.
- Type: string
- Possible Values: NONE, NEGLECT, MP2
- Default: NONE
MP2_AMPS_PRINT¶
Do print the MP2 amplitudes which are the starting guesses for RHF and UHF reference functions?
- Type: boolean
- Default: false
MP2_OS_SCALE¶
MP2 opposite-spin scaling value
- Type: double
- Default: 1.20
MP2_SS_SCALE¶
MP2 same-spin scaling value
- Type: double
- Default: 1.0/3.0
NEW_TRIPLES¶
Do use new triples?
- Type: boolean
- Default: true
NUM_AMPS_PRINT¶
Number of important
and
amplitudes to print
- Type: integer
- Default: 10
PAIR_ENERGIES_PRINT¶
Do print MP2 and CCSD pair energies for RHF references?
- Type: boolean
- Default: false
PROPERTY¶
The response property desired. Acceptable values are POLARIZABILITY (default) for dipole-polarizabilities, ROTATION for specific rotations, ROA for Raman Optical Activity, and ALL for all of the above.
- Type: string
- Possible Values: POLARIZABILITY, ROTATION, MAGNETIZABILITY, ROA, ALL
- Default: POLARIZABILITY
RESTART¶
Do restart the coupled-cluster iterations from old
- Type: boolean
- Default: true
R_CONVERGENCE¶
Convergence criterion for wavefunction (change) in CC amplitude equations.
- Type: conv double
- Default: 1e-7
SEMICANONICAL¶
Convert ROHF MOs to semicanonical MOs
- Type: boolean
- Default: true
SPINADAPT_ENERGIES¶
Do print spin-adapted pair energies?
- Type: boolean
- Default: false
T2_COUPLED¶
- Type: boolean
- Default: false
T3_WS_INCORE¶
Do build W intermediates required for cc3 in core memory?
- Type: boolean
- Default: false
Expert¶
AO_BASIS¶
The algorithm to use for the
terms If AO_BASIS is NONE, the MO-basis integrals will be used; if AO_BASIS is DISK, the AO-basis integrals stored on disk will be used; if AO_BASIS is DIRECT, the AO-basis integrals will be computed on the fly as necessary. NB: The DIRECT option is not fully implemented and should only be used by experts. Default is NONE. Note: The developers recommend use of this keyword only as a last resort because it significantly slows the calculation. The current algorithms for handling the MO-basis four-virtual-index integrals have been significantly improved and are preferable to the AO-based approach.
- Type: string
- Possible Values: NONE, DISK, DIRECT
- Default: NONE
FORCE_RESTART¶
Do restart the coupled-cluster iterations even if MO phases are screwed up?
- Type: boolean
- Default: false