Analytic static structure factors and pair-correlation functions for the unpolarized homogeneous electron gas

We propose 3 simple and accurate model for the electron static structure fa ctors (and corresponding pair-correlation functions) of the three-dimension al unpolarized homogeneous electron gas. Our spin-resolved pair-correlation function is built up with a combination of analytic constraints and fittin g procedures to quantum Monte Carlo data, and, in comparison to previous at tempts, (i) fulfills more known integral and differential properties of the exact pair-correlation function, (ii) is analytic both in real and in reci procal space, and (iii) accurately interpolates the newest, extensive diffu sion-Monte Carlo data of Ortiz, Harris, and Ballone [Phys. Rev. Lett. 82, 5 317 (1999)]. This can be of interest for the study of electron correlations of real materials and for the construction of new exchange and correlation energy density functionals.