Computer Modeling of Extended PnX3n + 2 Chains (X = F, Cl)

Abstract

Quantum-chemical calculations of extended nonmetal chains of general formula P_nX_{3n + 2} (X = F, Cl) and the corresponding infinite chains -(PX₃−PX₃)_∞- have been performed. It has been shown that all high-symmetry P_nX_{3n + 2} structures (n = 2–9) correspond to minima of the PES. Rotation around the P-P bond for fluoro derivatives is a low-barrier process; in the case, of chloro derivatives, it is accompanied by dissociation of the molecule. Calculations of the phonon spectrum for the infinite chain have demonstrated that both -(PX₃−PX₃)_∞- structures exhibit dynamic stability. According to calculations of the electronic band structure, such chains are wide-gap semiconductors.