GAP interatomic potential for CNa

This is a Gaussian approximation potential (GAP [1]) for carbon and sodium. The potential can be used to model sodium in carbon materials, including hard carbon, C60, defected graphite and amorphous carbon. This potential is composed of a reference carbon GAP [2] and a delta-GAP which represents the energy (or forces) difference induced by Na insertion into carbon matrices.

It has been fitted with gap_fit [3] by generating a new database of atomic structures containing dimers, C60 isomers, nanoporous carbon, defected graphite and amorphous carbon. 

The calculations were carried out at the PBE level of theory [4] using the VASP code [5, 6]. This potential uses 2-body (distance_2b) and SOAP (soap_turbo) [7, 8] descriptors. The files can be used both with QUIP/GAP (compiled with the soap_turbo librairies) and TurboGAP [9].

A reference to the relevant paper with more details and applications of the potential will be published here when they are available.