Quantum mechanical ab initio studies of the structures and stabilities of halogen azides XN3 (X = F, Cl, Br, I)

Abstract

We report theoretically predicted geometries, heats of formation, X-N 3 bond energies, and vibrational spectra of the halogen azides XN 3 (X=F, Cl, Br, I) and HN 3 calculated by quantum chemical methods at the Hartree-Fock and correlatcd levels using all-electron wave functions and effective-core potentials. The theoretical data are used to predict the geometries of BrN 3 and IN 3 , which have experimentally not been measured yet. A trans-bent (C s ) geometry is calculated for the halogen azides with a nearly constant bond angle of ∼172 o for the N 3 unit