Copper (II) complexes of 1-methyl-5-aminotetrazole with different energetic anions: syntheses, crystal structures and properties

Abstract

ABSTRRACT Three energetic copper (II) complexes, [Cu(1-MAT)2(HDNBA)2](DNBA)2 (1), [Cu(1-MAT)2](PA)2 (2) and [Cu(1-MAT)4(H2O)2](ClO4)2 (3) [1-MAT: 1-methyl-5-aminotetrazole; HDNBA: 3,5-dinitrobenzoic acid; PA: picric acid] were synthesized and characterized. The X-ray single-crystal diffraction results illustrate that the structure of the coordination compounds 1, 2 and 3 belong to the P21/c, P21212 and C2/m space group, respectively. The central copper ion forms a hexacoordinated octahedral structure with N and O atoms. All of them possess good thermal stability, with the thermal decomposition temperatures of 254°C (1), 272°C (2) and 322°C (3), respectively, due to their plenty of coordination bonds, intramolecular and intermolecular H-bonds. According to the results of impact sensitivity and friction sensitivity, these compounds are insensitive to impact (>40 J) and friction (>360 N), except the impact sensitivity of 3 is 2.7 J. The measured constant volume combustion energies of 1, 2 and 3 are 13480, 3537 and 7442 kJ mol−1, respectively.