Molcas Forum

cool@sm

Member

Registered: 2022-02-04

Posts: 2

Unphysical CMS-PDFT energies

Dear Users and Developers,

I am attempting a CMS-PDFT calculation preceded by a RASCI calculation (Openmolcas version 23.06). All possible CSFs (13) are included in the RASCI roots. Contrary to the RASCI roots, which are closely spaced, few CMS-PDFT roots are suspiciously high in energy (~ 2 Hartree) compared to other CMS roots. It happens with state-specific MCPDFT as well. However, for MCPDFT it happens for the random roots inbetween whereas for CMS-PDFT it happens for the highest lying roots. Is it common with MCPDFT methods or I am at fault here? Any suggestions or help is appreciated.

Best,
Soumitra

RASSCF Roots         CMS-PDFT Roots
-30224.82437003   -30238.33093525
-30224.82305389   -30238.32199491
-30224.82265541   -30238.31001293
-30224.82021054   -30238.30371894
-30224.79727910   -30238.28621462
-30224.82062273   -30238.27278825
-30224.80103674   -30238.24265755
-30224.80151642   -30238.22994110
-30224.76290824   -30238.14074355
-30224.80001040   -30238.11677148
-30224.68491166  -30236.37662427
-30224.65684367  -30236.32407280
-30224.62742832  -30236.16388418

Input:

>> COPY $CurrDir/../../../Molecule.ScfOrb INPORB

&RASSCF
cionly
Spin
1
Symmetry
2
nActEl
10 1 1
Typeindex
CIRoots
13 13 1
Iter
200 100
LUMORB
SupSym
2
3 8 9 10
2 42 43
3
1 4
2 23 24
1 26
2
1 9
1 10
3
1 4
2 23 24
1 26
CMSI

&MCPDFT
KSDFT
T:PBE
MSPD