AO DM

Hello,
I need to get access to the state density matrix in the AO basis, and I learned from other question posted here that it is not available for the ADC(2) method.
So I was wondering, please, if any of these possibilities may be available:

1) Help me adding the code for the DM for ADC(2)
2) If there is another excited-state method (with similar quality than ADC(2)) coded in MRCC, for which the DM is already available.

Thanks a lot!

Dear Edums,

this feature will be available with the ADC(2) gradient. Unfortunately, I work alone on the excited-state implementations, and now this project has a lower priority. In answer to your questions:

1. I have no idea how you want to manage this. That would be a rather complex project.
2. In principle, it could be extracted from the four-center implementation of the CC2 or CCSD methods. However, no one has tried this before in practice and this implementation is not designed for such a lower-order CC methods. It means that, even if it could be done, it would only be available for very small molecules.

Best regards,
David

Dear David,
thank you for your answer. I see the difficulties that you are mentioning.
At this point it would be enough for me to be able to calculate the electrostatic potential with an excited state density. Do you think it might be possible to compute the electrostatic potential on a grid using CC2 (or other method close to ADC(2) if not) based on the excited state density?
Thanks a lot