Undocumented Q-chem features¶
Multi-state FED¶
FED can be calculated using more than 2 states. This is using diabatization interface so it is needed to create a $localized_diabatization section to define the states to be used. When using multi-state FED a standard FED is also calculated.
Minimum set of keywords needed for multi-FED
$rem
...
sts_fed True ! activate FED calculation
sts_multi_nroots 4 ! number of states to be included in the FED
sts_multi_print 1 ! (or 2 for more information)
sts_donor 1-18 ! range of atoms in donor fragment
sts_acceptor 19-36 ! range of atoms in acceptor fragment
$end
$localized_diabatization
adiabatic states
1 2 3 4 ! state number of the sates to be included in the calculation
$end
full example for naphthalene dimer:
$molecule
0 1
C 0.0000000000 0.7076000000 0.0001000000
C 0.0000000000 -0.7076000000 0.0000000000
C 1.2250000000 1.3944000000 0.0000000000
C 1.2250000000 -1.3944000000 0.0001000000
C -1.2250000000 1.3943000000 0.0000000000
C -1.2250000000 -1.3943000000 0.0000000000
C 2.4327000000 0.6959000000 -0.0001000000
C 2.4327000000 -0.6958000000 0.0000000000
C -2.4327000000 0.6958000000 0.0000000000
C -2.4327000000 -0.6958000000 -0.0001000000
H 1.2489000000 2.4821000000 -0.0001000000
H 1.2489000000 -2.4822000000 0.0001000000
H -1.2490000000 2.4821000000 0.0001000000
H -1.2489000000 -2.4822000000 -0.0001000000
H 3.3732000000 1.2391000000 -0.0001000000
H 3.3733000000 -1.2390000000 -0.0001000000
H -3.3732000000 1.2390000000 0.0000000000
H -3.3733000000 -1.2390000000 -0.0001000000
C 0.0000000000 0.7076000000 4.0001000000
C 0.0000000000 -0.7076000000 4.0000000000
C 1.2250000000 1.3944000000 4.0000000000
C 1.2250000000 -1.3944000000 4.0001000000
C -1.2250000000 1.3943000000 4.0000000000
C -1.2250000000 -1.3943000000 4.0000000000
C 2.4327000000 0.6959000000 3.9999000000
C 2.4327000000 -0.6958000000 4.0000000000
C -2.4327000000 0.6958000000 4.0000000000
C -2.4327000000 -0.6958000000 3.9999000000
H 1.2489000000 2.4821000000 3.9999000000
H 1.2489000000 -2.4822000000 4.0001000000
H -1.2490000000 2.4821000000 4.0001000000
H -1.2489000000 -2.4822000000 3.9999000000
H 3.3732000000 1.2391000000 3.9999000000
H 3.3733000000 -1.2390000000 3.9999000000
H -3.3732000000 1.2390000000 4.0000000000
H -3.3733000000 -1.2390000000 3.9999000000
$end
$rem
jobtype sp
exchange b3lyp
basis sto-3g
cis_convergence 14
cis_n_roots 6
cis_singlets True
cis_triplets False
sts_fed True
sts_multi_nroots 4
sts_multi_print 1
sts_donor 1-18
sts_acceptor 19-36
$end
$localized_diabatization
adiabatic states
1 2 3 4
$end
expected multi-FED output
FED MULTISTATE ANALYSIS
Within CIS/TDA Singlet Excited States:
Localized diabatization specification
1 2 3 4
------------------------------------------------------------------------------
4 excited states are requested ...
1 LE (donor) state(s) found
2 CT state(s) found
1 LE (acceptor) state(s) found
------------------------------------------------------------------------------
Excitation Energy (eV) and Fragment-X Difference of 4 Diabatic States
------------------------------------------------------------------------------
n Excitation dX
----- ------------ ------------
1 4.52780500 -0.00000449
2 4.54916620 0.00000479
3 5.19733066 -1.93705111
4 5.19733075 1.93705270
------------------------------------------------------------------------------
Matrix Elements of Diabatic Hamiltonain
------------------------------------------------------------------------------
diabatH(1,2) = -2.672379E-17
diabatH(1,3) = -8.865129E-06
diabatH(1,4) = 9.37914E-06
diabatH(2,3) = -4.560166E-07
diabatH(2,4) = -1.565519E-06
diabatH(3,4) = 0.01839572