Questions tagged [mrcc]
For questions about (or involving) the MRCC electronic structure software package.
6
questions
17
votes
3
answers
437
views
How is "basis set projection" done?
I recently came across something called the basis set projection in Q-chem's manual. What it seems to do is to take the converged SCF in a smaller basis set, and then "projects" that onto a ...
- 5,499
9
votes
2
answers
630
views
What are Pair Natural Orbitals?
Recently, I came across electron correlation methods that use local pair natural orbitals (LPNOs) or domain-based local pair natural orbitals (DLPNO), such as DLPNO-MP2, DLPNO-CCSD etc. The dynamic ...
- 5,499
11
votes
2
answers
529
views
Analytic gradient for DLPNO-CCSD
Is there a formula for analytical gradients (for geometry optimization) for the DLPNO-CCSD method? I ask because I know that it is not implemented in ORCA. Maybe PNO-CCSD is implemented in MRCC or ...
- 3,629
8
votes
1
answer
106
views
Interfacing MRCC with CFOUR for dynamic polarizability
I have asked this question on the MRCC forum but did not get an answer.
I am trying to understand how to use CFOUR with the MRCC program for computing dynamic polarizability. To begin with, I am ...
- 275
16
votes
3
answers
396
views
How to calculate homolytic bond dissociation energies?
An experimental colleague asked me how hard it would be to calculate homolytic bond-dissociation energies for different phosphonates which are involved in a Hydrophosphination. The compounds include ...
- 7,744
20
votes
3
answers
316
views
What is the largest system that has been studied by the coupled cluster method?
This is parallel to the analogous question about the largest DFT calculation: What is the largest material that has been studied using density functional theory?
I assume we allow high performance ...
- 3,629