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You can choose an avatar and change the default style by going to "Profile" → "Personality" or "Display".#1 2024-12-12 16:36:51
- vkj
- Member
- Registered: 2019-04-10
- Posts: 29
SS/MS-CASPT2 gradients and NACs (Clarification)
Dear developers,
In the manual of Openmolcas it states:
All quasi-degenerate variants of CASPT2 support the analytical gradients and NAC, as well as RASPT2. Does this mean that these features are not supported for NON-quasidegenerate CASPT2 flavours like SingleState and MultiState ? Or they are availble for all flavours of CASPT2 ?
Many thanks
VKJ
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#2 2024-12-20 17:19:31
- matthew-hennefarth
- Member
- From: University of Chicago
- Registered: 2024-11-10
- Posts: 5
Re: SS/MS-CASPT2 gradients and NACs (Clarification)
NACs are mathematically not defined for SS-CASPT2. I believe Multi-State is considered a form of quasi-degenerate CASPT2.
Analytical gradients are available for
SS-CASPT2
MS-CASPT2
XMS-CASPT2
XDW-CASPT2
RMS-CASPT2
NACs are available for
MS-CASPT2
XMS-CASPT2
XDW-CASPT2
RMS-CASPT2
Note that for the quasi-degenerate CASPT2, I believe they are only implemented with density fitting and without the IPEA shift (see this article).
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