Five optimized stable 1H-3-nitro-5-amido-1,2,4-triazole (1H-ANTA) dimers were found on the potential energy surface and their electronic structures were obtained by using density function theory (DFT) method at the B3LYP/6-311＋＋G** level. The intermolecular interaction energy was calculated with basis set superposition error correction and zero point energy correction. The greatest binding energy of the dimer is 70.63 kJ/mol. Charges are transferred mainly to the triazole ring. The stability order deduced from the hydrogen bond intensity is consistent with that from the dimer binding energy. The hydrogen bond is the dominant form of 1H-ANTA intermolecular interaction. Based on the vibrational analysis, the changes of thermodynamic properties from the monomer to dimer with the temperature ranging from 200.0～800.0 K were obtained using the statistical thermodynamic method. It is found that the dimerization process of all five dimers can occur spontaneously in the researching temperature range.

Key words: 3-nitro-5-amido-1,2,4-triazole, intermolecular interaction, density functional theory, thermodynamic properties