Journal of Molecular Structure: THEOCHEM
Volume 305
10 March 1994
Pages 225-239
DOI: 10.1016/0166-1280(94)80158-4
Copyright © 1994 Published by Elsevier Science B.V. All rights reserved.

A theoretical study of the geometrical structure and energy inversion barriers of the cyanopnictogens NC-XY2 (X = N or P; Y = H, F, Cl or Br)

V. A. Glezakou, S. T. Kapellos and A. Mavridis1

Laboratory of Physical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistemiopolis, Athens 15771, Greece

Received 6 August 1993;  accepted 20 August 1993.  Available online 12 November 2001.


The structural properties and inversion barriers of the pnictogens (NC-XY2; X = N or P, Y = H, F, Cl or Br) were obtained through ab initio SCF and CI techniques using several basis sets. The geometries of the ground- and transition-state structures were fully optimized at the SCF level, and CISD calculations were performed on the SCF optimum geometries. All molecules have a pyramidal ground state of symmetry 1A'(Cs), and have a bent molecular spine, the angle NCX deviating from linearity by about 5°. For the phosphorous halocyanamides (NC-PX2) two transition structures were detected, the traditional trigonal planar structure and a T-shaped one, both of C2v symmetry. An attempt was made to rationalize our findings by employing the state characteristics of the CN and XY2 fragments.

1 Corresponding author.