Internal Rotation Barriers for Hydrazine and Hydroxylamine fromAb InitioLCAOmdash;MOmdash;SCF Wavefunctions

摘要

LCAOmdash;MOmdash;SCFab initiowavefunctions with atomic basis orbitals of doublehyphen;zeta accuracy have been constructed for N2H4and NH2OH and the potentialhyphen;energy curves versus internalhyphen;rotation angle have been determined. Similar wavefunctions for CH3CH3, CH3OH, CH3NH2, and H2O2, reported previously, showed a quantitatively useful correlation with experimental barrier heights and shapes. Since experimental information on the N2H4and NH2OH barriers is incomplete or unknown, the theoretical results presented here may help guide experimental work. Decomposition of the total energy into onehyphen; and twohyphen;electron components has been found previously to help elucidate the physical origin of the rotational barrier, and results for the species studied here are given. The wavefunctions presented here (and those reported previously for the species noted above) are the most accurate available for molecules possessing a rotational barrier about a single bond, and comparison is made with the results of the other existingab initiowavefunctions.