Predicting the stability and electronic structure of alkali metal aurides

Axel M Gaona Carranza; Reyes Garcia Diaz; D M Hoat; Jesús M Siqueiros; Jonathan Guerrero-Sanchez

doi:10.1088/1361-648X/ac5d1a

Predicting the stability and electronic structure of alkali metal aurides

J Phys Condens Matter. 2022 Apr 8;34(23). doi: 10.1088/1361-648X/ac5d1a.

Authors

Axel M Gaona Carranza¹, Reyes Garcia Diaz², D M Hoat^{3

4}, Jesús M Siqueiros¹, Jonathan Guerrero-Sanchez¹

Affiliations

¹ Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Ensenada B. C., 22800, Mexico.
² CONACyT-Facultad de Ciencias Físico Matemáticas, Universidad Autónoma de Coahuila, Unidad Camporedondo, Edif. A, 25000, Saltillo, Coahuila, Mexico.
³ Institute of Theoretical and Applied Research, Duy Tan University, Ha Noi 100000, Vietnam.
⁴ Faculty of Natural Sciences, Duy Tan University, Da Nang 550000, Vietnam.

PMID: 35276690
DOI: 10.1088/1361-648X/ac5d1a

Abstract

Density functional theory calculations of phonon modes predict that some compounds of the alkali metal aurides family, general formulaA₂MAu₆(A= K, Rb or Cs;M= Ti, Zr, Hf, Sn or Pb), have stable three-dimensional phase with a double perovskite-type structure and cubicFm3¯mspace group (K₂PtCl₆-type). Bader's charge analysis shows that most electron density is located within the six atoms at the octahedra vertices like double perovskite halides. However, the short spacing between Au anions enables d-orbital interactions between them. Compounds of this family, with group 4 metals only, carry conduction states around the Γ point (k= 0). On the other hand, compounds with group 14 metals possess more conduction states around all the Brillouin zone and have electron pockets in their band structures. These compounds provide further insights into the unusual anionic behavior of gold and present other alternatives for the construction of divergent nanodevices.

Keywords: alkali metal aurides; anionic behavior; electronic structure; stability.