Paper Title
First Principles Study of Electronic and Optical Properties of BaF2

Abstract
Barium fluoride (BaF2) is an important member of alkaline-earth fluorides for its intrinsic optical properties. The structural, optical properties, phonon frequencies, and dielectric constants have been investigated with ab initio density functional theory (DFT) method and Density functional perturbation theory (DFPT). The calculations had been done using a first principle code Quantum espresso, implemented ultra-soft pseudo-potentials (US-PPs) and projector augmented wave (PAW) data sets with the local density approximation (LDA) and the Generalized Gradient Approximation (GGA) for the exchange-correlation. The optimized lattice parameters, phonon frequencies at main symmetry points of the Brillouin zone and dielectric constants resulting of pseudo-potentials used were in a good agreement with other theoretical and experimental data. Keywords - Barium Fluoride, Dielectric Constants, Pseudo-Potentials, Quantum Espresso.