In addition to the standard CIS job controls variables described in Section 7.2.8, there are several additional $rem variables to specify for an ALMO-CIS/ALMO-CIS+CT calculation.
LOCAL_CIS
LOCAL_CIS
Invoke ALMO-CIS/ALMO-CIS+CT.
TYPE:
INTEGER
DEFAULT:
0
OPTIONS:
0
Regular CIS
1
ALMO-CIS/ALMO-CIS+CT without RI(slow)
2
ALMO-CIS/ALMO-CIS+CT with RI
RECOMMENDATION:
2 if ALMO-CIS is desired.
NN_THRESH
NN_THRESH
The distance cutoff for neighboring fragments (between which CT is enabled).
TYPE:
INTEGER
DEFAULT:
0
OPTIONS:
0
Do not include interfragment transitions (ALMO-CIS).
Include interfragment excitations between pairs of fragments the distances between whom
are smaller than Bohr (ALMO-CIS+CT).
RECOMMENDATION:
None
EIGSLV_METH
EIGSLV_METH
Control the method for solving the ALMO-CIS eigen-equation
TYPE:
INTEGER
DEFAULT:
0
OPTIONS:
0
Explicitly build the Hamiltonian then diagonalize (full-spectrum).
1
Use the Davidson method (currently only available for restricted cases).
RECOMMENDATION:
None
Example 12.45 ALMO-CIS+CT calculation ( a) for all the states of a helium dimer.
$molecule 0 1 -- 0 1 He 2.8 0. 0. -- 0 1 He 0. 0. 0. $end $rem BASIS gen AUX_BASIS rimp2-cc-pvdz PURECART 1111 METHOD hf SYM_IGNORE true SYMMETRY false FRGM_METHOD stoll CIS_N_ROOTS 8 CIS_TRIPLETS false LOCAL_CIS 2 ! use RI for ALMO-CIS NN_THRESH 10 $end $rem_frgm cis_n_roots 0 $end $basis **** HE 0 S 3 1.000000 3.84216340D+01 2.37660000D-02 5.77803000D+00 1.54679000D-01 1.24177400D+00 4.69630000D-01 S 1 1.000000 2.97964000D-01 1.00000000D+00 SP 1 1.000000 4.80000000D-02 1.00000000D+00 1.00000000D+00 **** $end