Documentation of SOC for EOM-CC

Section of the current manual says:

" Calculations of L-edge spectra using state-interaction approach entails a two-step procedure. First, Q-Chem computes necessary CVS-EOM states and SOCs. In the second step, the spin-orbit perturbed spectrum is computed by a post-processing script. Scripts, detailed instructions, and examples can be found here ."

Where is that “here” pointing to? I recall somewhere the manual used to indeed provide detailed information on the new SOC module by Pavel Pokhilko and Evgeny Epifanovsky but I cant seem to find it anymore.

The reference should be to M. L. Vidal, Marta L. Vidal / l-edge · GitLab. That’s correct in our (developer) LaTeX manual so should be correct in PDF going forward, if you’re looking at HTML manual will you please give me a URL? It’s possible there was a LaTeX-to-HTML conversion error.

Thank you - I am looking at the HTML version here: 7.11.8 EOM-CC Calculations of Core-Level States‣ 7.11 Coupled-Cluster Excited-State and Open-Shell Methods ‣ Chapter 7 Open-Shell and Excited-State Methods ‣ Q-Chem 6.1 User’s Manual

There is no hyperlink nor reference so there may indeed be a conversion error.

I have reformatted the Bibtex entry so I think this will be fixed in next release.

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The CVS EOM-CC SOC paper is here that should be in the manual:
There we extended the state-interaction approach for L-edges along with other things, such as Dyson orbitals.

Yep I was aware of the paper. I was needing more specific details about how access the functionality in QChem and helpful scripts that were promised by the manual.

Q-Chem functionality and the way to get it is pretty much the same as without CVS. The state interaction can be crafted by hand by collecting all the printed matrix elements. But it is not very convenient when the number of interacting states is large, so Marta wrote that script.

I think its not documented even for non-CVS? I was unable to find it, at least.

I wrote that part a while ago: Section
I recommend also to look at the key paper to see how it works:

Aha - that is exactly the section of the manual I remembered but couldn’t find. It didn’t show up in the first few entries when I look up SOC in the search bar and only now I see the small arrow at the bottom to look at more…

Maybe it’d be a good idea to make that arrow bigger. I’ll indeed take a look at that paper - thank you two for your help.

You can always download the PDF manual, which is easily searchable and which has a hyperlinked TOC to take you to different sections.