Thermodynamic Properties of Some Functionally Substituted Azoles in the Condensed State

Results are presented from measuring the heat capacity in the condensed state via low-temperature adiabatic calorimetry in the range of 5–370 K for 1-ethyl-4-nitro-1,2,3-triazole, 1-methyl-4-nitro-1,2,3-triazole, 2-methyl-4-nitro-1,2,3-triazole, and 5-(1-adamantyl)tetrazole and in the range 80–370 K for 1-benzyl-4-phenyl-1Н-1,2,3-triazole; and 1,3-bis(1-methyl-1 H -tetrazol-5-yl)propane. The thermodynamic parameters of the phase transitions of compounds in the studied ranges of temperature are determined. The thermodynamic parameters of melting are determined by DSC for three compounds with melting points above 370 K: 2-methyl-4-nitro-1,2,3-triazole, 1-benzyl-4-phenyl-1 H -1,2,3-triazole, and 1,3-bis(1-methyl-1 H -tetrazol-5-yl)propane. The standard thermodynamic functions (heat capacity, entropy, reduced enthalpy, and Gibbs energy) of the studied compounds in the crystalline and liquid states are calculated using the obtained data.