Quantum Mechanical Studies on Chemical Reactivity and Ballistic Chemistry. I. CNDO/2 Calculations on Pyrrole and on Its Aza Derivatives

摘要

As part of a program of quantum-chemical calculations on chemical reactivity and ballistic chemistry, the authors have calculated the elctronic structures of pyrrole and its aza derivatives by the CNDO/2 method. The variation with structure of the calculated electron-distributions for these molecules can be understood in terms of organic chemical concepts such as resonance and inductive effects, with sigma-pi electron repulsion apparently playing a role in some cases. The relative merits of idealized and experimental geometrical models in calculations of this type are discussed. Solvent and other effects which may affect the reliability of the calculated electron distributions are discussed. Comparisons between calculated and observed dipole moments are also given. (Author)