Charge/Electron transfer with QMD FSSH module

[Bushra Alam]

Hello everyone.

I'm trying to study charge transfer dynamics between a donor-acceptor pair using the FSSH implementation in NWChem. It's a part of the NAMD methods under the QMD category.

1) I have submitted a calculation with a donor and acceptor molecule but not sure how to track charges or populations of the two molecules separately. Is there a way to do this yet? I have requested the Mulliken properties option within the QMD block but it doesn't get printed.

2) In the following 2020 paper, Figure 2 shows the variation in the populated states but since I have a geometry consisting of 2 systems, the excited state refer to the supersystem states rather than those localised on any one unit.

I have attached an input file for a better idea of what I'm trying.

Any insights are welcome. Thank You!

P.S - NWchem has an independent method for studying Electron Transfer in a Marcus Theory fashion. I'm aware of that, but I'm trying to study the dynamics of the transfer.

[Edoardo Aprà]

1) Add mulliken in the dft input section

dft

  xc b3lyp

  mulliken

end

https://nwchemgit.github.io/Density-Functional-Theory-for-Molecules.html#mulliken-mulliken-analysis

[Bushra Alam]

Hello,

Thank you for the information regarding the Mulliken charges, it was very helpful.

Do you know (of the top of your head), if I can use fragments in a QMD FSSH calculation? It would help me to define donor and acceptor fragments with the help of charges. I will try it out anyway, but I'm asking in case it has been tried, in your knowledge.

Best,

Bushra