A COMPUTATIONAL STUDY OF AZINE, AZOETHENE, AND DIIMINE LINKAGES IN THE POLY OLIGOAZINE SYSTEM/

Hartree-Fock (HF) and molecular mechanics calculations were performed on linear azine oligomers and model compounds. The rotational energy c urves for the model compounds formaldazine, H2C = N-N = CH2, ethenyl d iazene, H2C = CH-N = NH, and ethanediimine, HN = CH-CH = NH were calcu lated for a variety of basis sets at the HF and MP2 level. In all of t hese cases the rotational energy barriers are quite different from but adienes or aza-substituted butadienes because of the lone pair-lone pa ir interaction of the adjacent nitrogen atoms. The results on the mode l compounds were used to generate a set of molecular mechanics (MM) pa rameters that are appropriate for linear oligo- and polyazines. Compar ison of the geometries of the HF results and MM results for the oligoa zines showed that the two methods gave comparable results. (C) 1994 by John Wiley and Sons, Inc.