Structural and bonding properties of intermetallic compounds ARh2P2 (A=Ca, Sr, Ba)

Self-consistent band structure calculations have been performed for tetragonal CaRh2P2, SrRh2P2 and BaRh2P2 compounds with a ThCr2Si2-type structure. The calculated ground-state properties of these compounds are in good agreement with experimental results. An analysis of the bonding situation in these compounds has been done in terms of the band structure and the electron charge density plots. The possibility of phase transitions in SrRh2P2 and BaRh2P2 has been studied from the occurrence of two total energy minima with respect to the c/a ratio.