Libxc interface?

[susilehtola]

Hi,

referring to J. Chem. Phys. 154, 214302 (2021)

we later realized that the BP86 versions in ORCA and MRChem are not identical, implying that a comparison of GTO to MW at the BP86 level would be affected by differences in the implementation of the functional, which our tests indicated could amount to several kcal/mol, when approaching the CBS limit

it sounds like MRChem would greatly benefit from an interface to Libxc which offers a consistent, reusable set of functionals across >40 programs including ORCA. Would you be interested in such an interface?

[ilfreddy]

This is indeed something we have contemplated doing for a long time. The point of XCFun was automatic differentiation to go to high order response. This has so far not yet happened. But in the meantime the development of XCFun has more or less stagnated whereas LibXC is the de-facto standard.
I am also involved, with a minor role, in a ITN application where MRChem will be used for benchmarks. The need to use more modern fuctionals in MRChem is very rellevant for that too!