Effects of pseudopotentials and exchange-correlation functionals on phase transition of LaH10. (January 2022)

• Record Type: Journal Article
• Authors: Sura, Sumita; Verma, Ashok K.; Garg, Nandini
• Is Part Of: Solid state communications. Volume 341(2022)
• Publication Date: 2022-01
• Subjects: Density functional theory -- Structural phase transitions -- High pressure; Solid state chemistry -- Periodicals; Solid state physics -- Periodicals; Chimie de l'état solide -- Périodiques; Physique de l'état solide -- Périodiques; 530.41
• DOI: 10.1016/j.ssc.2021.114583
• Languages: English
• ISSNs: 0038-1098

Abstract

Abstract: To assess the effects of pseudopotentials and exchange-correlation functionals on trigonal to face-centered cubic phase transition of LaH10, we performed density functional theory based first-principles calculations by employing three-types of pseudopotentials with LDA (local density approximation) and GGA (generalized gradient approximation) exchange-correlation functionals. We found that the lattice parameters such as cell angle or cell volume and phase transition pressure exhibit a significant variation with LDA and GGA functionals whereas they exhibit a weak dependence on the pseudopotentials. In general, LDA calculations result in a lower phase transition pressure than GGA calculations. We also investigated the effects of pseudopotentials and exchange-correlation functionals on the electronic properties by calculating the total and partial density of state functions for face-centered cubic phase of LaH10 at 150 GPa. Computed electronic densities of states at the Fermi level are found to exhibit a weak dependence on the exchange-correlation functionals. Highlights: Lattice properties of LaH10 exhibit a strong dependent on the exchange-correlation functionals. Trigonal to cubic phase transition pressure also exhibits a strong dependent on the exchange-correlation functions. Computed density of state functions exhibits a weak dependence on the exchange-correlations.