Author:
Guevara-Vela José Manuel,Gallegos Miguel,Rocha-Rinza Tomás,Muñoz-Castro Álvaro,Kessler Peter L. Rodríguez,Martín Pendás Ángel
Abstract
Abstract
Context
The study of platinum (Pt) clusters and nanoparticles is essential due to their extensive range of potential technological applications, particularly in catalysis. The electronic properties that yield optimal catalytic performance at the nanoscale are significantly influenced by the size and structure of Pt clusters. This research aimed to identify the lowest-energy conformers for Pt$$_{18}$$
18
, Pt$$_{19}$$
19
, and Pt$$_{20}$$
20
species using Density Functional Theory (DFT). We discovered new low-symmetry conformers for Pt$$_{19}$$
19
and Pt$$_{20}$$
20
, which are 3.0 and 1.0 kcal/mol more stable, respectively, than previously reported structures. Our study highlights the importance of using density functional approximations that incorporate moderate levels of exact Hartree-Fock exchange, alongside basis sets of at least quadruple-zeta quality. The resulting structures are asymmetric with varying active sites, as evidenced by sigma hole analysis on the electrostatic potential surface. This suggests a potential correlation between electronic structure and catalytic properties, warranting further investigation.
Methods
An equivariant graph neural network interatomic potential (NequIP) within the Atomic Simulation Environment suite (ASE) was used to provide initial geometries of the aggregates under study. DFT calculations were performed with the ORCA 5 package, using functional approximations that included Generalized Gradient Approximation (PBE), meta-GGA (TPSS, M06-L), hybrid (PBE0, PBEh), meta-GGA hybrid (TPSSh), and range-separated hybrid ($$\omega $$
ω
B97x) functionals. Def2-TZVP and Def2-QZVP as well as members of the cc-pwCVXZ-PP family to check basis set convergence were used. QTAIM calculations were performed using the AIMAll suite. Structures were visualized with the AVOGADRO code.
Funder
Ministerio de Ciencia e Innovación
Dirección General de Cómputo y de Tecnologías de Información y Comunicación
Fondo Nacional de Desarrollo Científico y Tecnológico
Instituto Potosino de Investigación Científica y Tecnológica
Publisher
Springer Science and Business Media LLC