Improved generalized gradient approximation for positron states in solids

Abstract

Several first-principles calculations of positron-annihilation characteristics in solids have added gradient corrections to the local-density approximation within the theory by Arponen and Pajanne [Ann. Phys. (N.Y.) 121, 343 (1979)] since this theory systematically overestimates the annihilation rates. As a further remedy we propose to use gradient corrections for other local density approximation schemes based on perturbed hypernetted-chain and on Quantum Monte Carlo results. Our calculations for various metals and semiconductors show that the proposed schemes generally improve the positron lifetimes when they are confronted with experiment. We also compare the resulting positron affinities in solids with data from slow-positron measurements.

16 pages, 5 figures, 3 tables

References in corpus (6)

• Topological Insulators with Inversion Symmetry
• Positron lifetime calculation of the elements of the periodic table
• Modeling the momentum distributions of annihilating electron-positron pairs in solids
• Surfaces of colloidal PbSe nanocrystals probed by thin-film positron annihilation spectroscopy
• Renormalization of f-levels away from the Fermi energy in electron excitation spectroscopies: Density functional results of Nd${}_{2-x}$Ce${}_x$CuO${}_4$
• Sensitiveness of the ratio between monovacancy and bulk positron lifetimes to the approximations used in the calculations: Periodic behaviour

Cited by in corpus (10)

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• Accurate theoretical prediction on positron lifetime of bulk materials
• Two-component density functional theory for muonic molecules: Inclusion of the electron-positive muon correlation functional
• Quantum Monte Carlo study of positron lifetimes in solids
• Quantifying errors of the electron-proton/muon correlation functionals through the Kohn-Sham inversion of a two-component model system
• First-principles study of the impact of grain boundary formation in the cathode material LiFePO4
• Exploring positron characteristics utilizing two new positron-electron correlation schemes based on three electronic-structure calculation methods
• Exotic Harmonium Model: Exploring Correlation Effects of Attractive Coulomb Interaction