{"title":"Electronic states and fermiology of H3Ge and Li3Ge","authors":"Saloni Sharma , Vijay Maurya , K.B. Joshi","doi":"10.1016/j.cocom.2025.e01072","DOIUrl":null,"url":null,"abstract":"<div><div>In this paper <em>ab-initio</em> characterization of electronic states, Fermiology and bonding of H<sub>3</sub>Ge and Li<sub>3</sub>Ge are presented. The Full Potential Linearized Augmented Plane Wave method is applied to study the structural properties, the vacancy migration enthalpy H<sup>M</sup> and lattice dynamics. The electronic properties such as band structure, density of states, directional Compton profiles and Fermi surface are presented. The low value of H<sup>M</sup>; 0.43 and 0.41 eV for H<sub>3</sub>Ge and Li<sub>3</sub>Ge, respectively, suggests faster diffusion, high atomic mobility and fast ion transport. The phonon dispersion of Li<sub>3</sub>Ge does not deliver imaginary frequencies. The electronic states reveal the metallic nature of both compounds. The comparison of band structure of H<sub>3</sub>Ge with that of synthetic H-sublattice reveal that Ge gives rise to the formation of bands around Fermi energy and responsible for the metallic behavior. In H<sub>3</sub>Ge the Fermi surfaces constituted by two bands are electron-like while in Li<sub>3</sub>Ge three bands constitute the Fermi surfaces which are hole-like. The quantum oscillations determined using de Haas Van Alphen effect shows fine features of the Fermi surface. Directional Compton profiles show more anisotropy and occupied states in Li<sub>3</sub>Ge than H<sub>3</sub>Ge. The J<sub>110</sub>-J<sub>100</sub> anisotropy is higher than J<sub>111</sub>-J<sub>100</sub> in both compounds. These observations are well captured by the branches of FS of the compounds. The auto correlation function gives 3.61 and 7.24 a.u bond lengths of H-H, Ge-Ge bonds in H<sub>3</sub>Ge. Similarly 4.48 and 8.96 a.u. bond lengths are obtained for Li-Li and Ge-Ge bonds in Li<sub>3</sub>Ge. The Ge-Ge, H-H/Li-Li interactions dominate in formation of bands and bonds in the two compounds.</div></div>","PeriodicalId":46322,"journal":{"name":"Computational Condensed Matter","volume":"44 ","pages":"Article e01072"},"PeriodicalIF":3.9000,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Computational Condensed Matter","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2352214325000711","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"PHYSICS, CONDENSED MATTER","Score":null,"Total":0}
引用次数: 0
Abstract
In this paper ab-initio characterization of electronic states, Fermiology and bonding of H3Ge and Li3Ge are presented. The Full Potential Linearized Augmented Plane Wave method is applied to study the structural properties, the vacancy migration enthalpy HM and lattice dynamics. The electronic properties such as band structure, density of states, directional Compton profiles and Fermi surface are presented. The low value of HM; 0.43 and 0.41 eV for H3Ge and Li3Ge, respectively, suggests faster diffusion, high atomic mobility and fast ion transport. The phonon dispersion of Li3Ge does not deliver imaginary frequencies. The electronic states reveal the metallic nature of both compounds. The comparison of band structure of H3Ge with that of synthetic H-sublattice reveal that Ge gives rise to the formation of bands around Fermi energy and responsible for the metallic behavior. In H3Ge the Fermi surfaces constituted by two bands are electron-like while in Li3Ge three bands constitute the Fermi surfaces which are hole-like. The quantum oscillations determined using de Haas Van Alphen effect shows fine features of the Fermi surface. Directional Compton profiles show more anisotropy and occupied states in Li3Ge than H3Ge. The J110-J100 anisotropy is higher than J111-J100 in both compounds. These observations are well captured by the branches of FS of the compounds. The auto correlation function gives 3.61 and 7.24 a.u bond lengths of H-H, Ge-Ge bonds in H3Ge. Similarly 4.48 and 8.96 a.u. bond lengths are obtained for Li-Li and Ge-Ge bonds in Li3Ge. The Ge-Ge, H-H/Li-Li interactions dominate in formation of bands and bonds in the two compounds.