Ab initio study of structures of hydrogen-bonded nitric acid complexes Original Research Article

The structures of the hydrogen-bonded complexes of nitric acid with various bases: CH4⋯H–ONO2, N2⋯H–ONO2, OC⋯H–ONO2, NO2⋯H–ONO2, (HNO3)2 and H3N⋯H–ONO2 are studied extensively by ab initio calculations at SCF and MP2 levels with various basis sets: 6-31G/SCF, 6-31G/MP2, 6-31G**/SCF, 6-31G**/MP2, 6-31+G**/SCF, 6-31+G**/MP2, 6-311+G**/SCF and 6-311+G**/MP2 and density functional B3LYP/6-31G(d,p) calculations. Full geometry optimization was made for the complexes studied. After the consideration of the strength of the hydrogen bond, the studied hydrogen-bonded complexes can be order as follows: H3N⋯H–ONO2, (HNO3)2,NO2⋯H–ONO2,OC⋯H–ONO2,N2⋯H–ONO2,CH4⋯H–ONO2.