GAP interatomic potential for PtAu:H nanoparticle simulation

<p><strong>Gaussian approximation potential</strong> (GAP) [1] for the <strong>platinum-gold-hydrogen </strong>system. It can be safely used to generate PtAu nanoparticles throughout the whole composition range and to hydrogenate them (add adsorbed H on the surface). For any other system, the accuracy and stability of the potential should be specifically tested (e.g., against reference DFT calculations). It has been fitted with&nbsp;<strong>gap_fit </strong>[2] by generating a new database of atomic structures containing:</p> <ol> <li>bulk PtAu structures, including 3x3x3 supercells with substitutional alloying as determined by cluster-expansion configurations generated by the CASM code [10];</li> <li>PtAu surface slabs, with random alloying and H adsorption at different coverages;</li> <li>iteratively generated PtAu clusters (nanoparticles), following a similar approach as in Ref. [3], and adding H coverage to those.</li> </ol> <p>The calculations were carried out at the&nbsp;<strong>PBE</strong> level of theory [4] using the VASP code [5,6]. This potential uses <strong>2-body</strong>&nbsp;(distance_2b) and&nbsp;<strong>SOAP-type descriptors</strong> (soap_turbo) [7,8]. The files can be used both with QUIP/GAP (compiled with the soap_turbo libraries) and <strong>TurboGAP</strong> [9]. The reference publication for this potential will be added in time (e.g., when a preprint is a valable, and then updated when a journal publication is available).</p> <p>Financial support from the Research Council of Finland and computational resources from CSC (the Finnish IT Center for Science) and Aalto University's Science-IT project are gratefully acknowledged.</p> <p><strong>References</strong></p> <ol> <li>A.P. Bart&oacute;k, M.C. Payne, R. Kondor, and G. Cs&aacute;nyi. Phys. Rev. Lett. 104, 136403 (2010).</li> <li>S. Klawohn, J.P. Darby, J.R. Kermode, G. Cs&aacute;nyi, M.A. Caro, and A.P. Bart&oacute;k. J. Chem. Phys. 159, 174108 (2023).</li> <li> <div>J. Kloppenburg, L.B. P&aacute;rtay, H. J&oacute;nsson, and M.A. Caro. J. Chem. Phys. 158, 134704 (2023).</div> </li> <li>J.P. Perdew, K. Burke and M. Ernzerhof. Phys. Rev. Lett. 77, 3865 (1996).</li> <li>VASP:&nbsp;<a href="http://vasp.at/">http://vasp.at</a></li> <li>G. Kresse and J. Furthm&uuml;ller. Phys. Rev. B 54, 11169 (1996).</li> <li>A.P. Bart&oacute;k, R. Kondor, and G. Cs&aacute;nyi. Phys. Rev. B 87, 184115 (2013).</li> <li>M.A. Caro. Phys. Rev. B 100, 024112 (2019).</li> <li>TurboGAP:&nbsp;<a href="http://turbogap.fi/">http://turbogap.fi</a></li> <li>https://prisms-center.github.io/CASMcode_docs</li> </ol>