Ab initio self-consistent field (SCF) and M0Der-Plesset correlationcorrection methods employing 6-31G^(**) basis set have been applied to the optimizations ofnitroamine dimers. The binding energies have been corrected...Ab initio self-consistent field (SCF) and M0Der-Plesset correlationcorrection methods employing 6-31G^(**) basis set have been applied to the optimizations ofnitroamine dimers. The binding energies have been corrected for the basis set superposition error(BSSE) and the zero-point energy. Three optimized dimers have been obtained. The BSSE correctedbinding energy of the most stable dimer is predicted to be - 31.85 kJ/mol at the MP4/6-31G^(**)//MP2/6-31G^(**) level. The energy barriers of the Walden conversion for - NH_2 group are 19.7kJ/mol and 18.3 kJ/mol for monomer and the most stable dimer, respectively. The molecularinteraction makes the internal rotation around N_1 - N_2 even more difficult. The thermodynamicproperties of nitroamine and its dimers at different temperatures have been calculated on the basisof vibrational analyses. The change of the Gibbs free energy for the aggregation from monomer to themost stable dimer at standard pressure and 298.2 K is predicted to be 14.05 kJ/mol.展开更多
文摘Ab initio self-consistent field (SCF) and M0Der-Plesset correlationcorrection methods employing 6-31G^(**) basis set have been applied to the optimizations ofnitroamine dimers. The binding energies have been corrected for the basis set superposition error(BSSE) and the zero-point energy. Three optimized dimers have been obtained. The BSSE correctedbinding energy of the most stable dimer is predicted to be - 31.85 kJ/mol at the MP4/6-31G^(**)//MP2/6-31G^(**) level. The energy barriers of the Walden conversion for - NH_2 group are 19.7kJ/mol and 18.3 kJ/mol for monomer and the most stable dimer, respectively. The molecularinteraction makes the internal rotation around N_1 - N_2 even more difficult. The thermodynamicproperties of nitroamine and its dimers at different temperatures have been calculated on the basisof vibrational analyses. The change of the Gibbs free energy for the aggregation from monomer to themost stable dimer at standard pressure and 298.2 K is predicted to be 14.05 kJ/mol.
