General purpose Gaussian approximation potential for CO

This is a Gaussian approximation potential (GAP [1]) for carbon and oxygen. The potential can be used to model oxygen-containing carbon materials, including oxygenated graphitic and amorphous carbons. It has been fitted with gap_fit [2] by recomputing the a-C database of Deringer and Csányi [3] at the PBE level of theory [4] using the VASP code [5,6] and augmenting it to include other atomic structures, namely: Dimers at closer interatomic separation than in [3], including O-O and C-O in addition to C-C C60 isomers Iteratively generated oxygen-containing carbon structures from low oxygen content up to approx. 50% oxygen content Environment independent ("fixed C6") vdW corrections are included via tabulated two-body interactions with a damped London-dispersion functional form (1/R^6 decay). The vdW interactions are damped both in the short range (similar to the Tkatchenko-Scheffler scheme [7], but without the environment dependence) and long range (hard cutoff at 20 Angstrom and soft cutoff at 17.5 Angstrom). The parameters are optimized to reproduce the typical vdW interactions in graphitic carbon. Future versions of the CO-GAP may include support for more sophisticated vdW corrections. For the underlying PBE fit, this potential uses 2-body (distance_2b) and 3-body (angle_3b) descriptors [2] plus SOAP-type descriptors (soap_turbo) [8,9], as implemented in the TurboGAP code [10]. The files can be used both with QUIP/GAP (and LAMMPS via the QUIP interface) and TurboGAP. The authors acknowledge funding from the Academy of Finland (grants 321713, 330488, 336304, 355301 and 358050) and computational resources from the Finnish Center for Scientific Computing (CSC) and Aalto University's Science IT project. A reference to the relevant paper with more details and applications of the potential will be published here when they are available. References A.P. Bartók, M.C. Payne, R. Kondor, and G. Csányi. Phys. Rev. Lett. 104, 136403 (2010). S. Klawohn, J.P. Darby, J.R. Kermode, G. Csányi, M.A. Caro, and A.P. Bartók. J. Chem. Phys.159, 174108 (2023). V.L. Deringer and G. Csányi. Phys. Rev. B 95, 094203 (2017). J.P. Perdew, K. Burke, and M. Ernzerhof. Phys Rev. Lett. 77, 3865 (1996). VASP: http://vasp.at G. Kresse and J. Furthmüller. Phys. Rev. B 54, 11169 (1996). A. Tkatchenko and M. Scheffler. Phys. Rev. Lett. 102, 073005 (2009). A.P. Bartók, R. Kondor, and G. Csányi. Phys. Rev. B 87, 184115 (2013). M.A. Caro. Phys. Rev. B 100, 024112 (2019). TurboGAP: http://turbogap.fi Contact Miguel A. Caro: [email protected] or [email protected]