The M06-2X/6-311G(d, p) and B3LYP/6-311G(d, p) density functional methods and electrostatic potential analysis were used for calculation of enthalpy of sublimation, crystal density and enthalpy of formation of some thermally stable explosives in the gas and solid phases. These data were used for prediction of their detonation properties including heat of detonation, detonation pressure, detonation velocity, detonation temperature, electric spark sensitivity, impact sensitivity and deflagration temperature using appropriate methods. The range of different properties for these compounds are: crystal density 1.51-2.01 gcm(-3), enthalpy of sublimation 346.4-424.7 kJmol(-1), the solid phase enthalpy of formation 500.4-860.6 kJmol(-1), heat of detonation 13.64-17.57 kJg(-1), detonation pressure 33.0-37.0 GPa, detonation velocity 8.5-9.5 kms(-1), detonation temperature 5488-6234 K, electric spark sensitivity 7.89-9.47 J, impact sensitivity 21-38 J, deflagration temperature 560-586 K and power [%TNT] 207-276. The results show that two novel energetic compounds N,N'-(diazene-1,2-diylbis(2,3,5,6-tetranitro-4,1-phenylene))bis(5-nitro-4H-1,2,4-triazol-3-amine) (DDTNPNT3A) and 1,1'-(diazene-1,2-diylbis(2,3,5,6-tetranitro-4,1-phenylene)) bis(3-nitro-1H-1,2,4-triazol-5-amine) (DDTNPNT5A) can be introduced as thermally explosives with high detonation performance.