Structural, electronic and elastic properties of KCaF3 and RbCaF3 for vacuum-ultraviolet-transparent lens materials

摘要: The first principles calculation within the full potential linearized augmented plane wave (FP-LAPW) method is applied to study structural, electronic and elastic properties of cubic perovskite-type compounds KCaF3 RbCaF3. exchange correlation effects are included through LDA, GGA modified Becke-Johnson (mBJ) potential. calculated structural such as equilibrium lattice constant, bulk modulus its pressure derivative in good agreement with available data. RbCaF3 have wide indirect band gaps they agree experimental values. constants, anisotropy factor, shear modulus, Young’s Poisson’s ratio obtained for time. elastically anisotropic B/G indicate that these ductile materials.