Dear all,
I tried to run the Mk-MRCCSD sample input file (Water molecule with symmetry) provided by PSI4 documentaion, and it ran successfully. The input file is shown below:
molecule o2 {
0 3
O
O 1 2.265122720724
units au
}
set {
basis cc-pvtz
}
set mcscf {
reference rohf
docc [3,0,0,0,0,2,1,1] # Doubly occupied MOs
socc [0,0,1,1,0,0,0,0] # Singly occupied MOs
}
set psimrcc {
corr_wfn ccsd # Do Mk-MRCCSD
frozen_docc [1,0,0,0,0,1,0,0] # Frozen MOs
restricted_docc [2,0,0,0,0,1,1,1] # Doubly occupied MOs
active [0,0,1,1,0,0,0,0] # Active MOs
frozen_uocc [0,0,0,0,0,0,0,0] # Frozen virtual MOs
corr_multp 1 # Select the Ms = 0 component
follow_root 1
wfn_sym B1g # Select the B1g state
}
energy('psimrcc')
The output file could be found here.
h2o-mkmrccsd.dat (21.9 KB)
However, if I use the symmetry C1 while keeping other parameters all the same, then the calculation energy became weird, and could not converge.
The input file is shown below:
memory 40GB
molecule o2 {
0 3
O
O 1 2.265122720724
units au
symmetry c1
}
set {
basis cc-pvdz
}
set mcscf {
reference rohf
docc [7] # Doubly occupied MOs
socc [2] # Singly occupied MOs
}
set psimrcc {
corr_wfn ccsd # Do Mk-MRCCSD
frozen_docc [2] # Frozen MOs
restricted_docc [5] # Doubly occupied MOs
active [2] # Active MOs
frozen_uocc [0] # Frozen virtual MOs
corr_multp 1 # Select the Ms = 0 component
follow_root 1
# wfn_sym B1g # Select the B1g state
}
energy('psimrcc')
The output file of symmetry C1 coud be found here.
h2o-mkmrccsd-c1.dat (19.8 KB)
I am new to PSI4, so if I make any mistake with the input file, please let me know. Thanks in advance.