Heat capacities and phase transitions of octahydro- 1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)

Abstract The heat capacities and enthalpies of phase transitions of the four known polymorphs of HMX have been determined over the temperature range 320 to 530 K. All the measurements were done using a Perkin-Elmer DSC-1B differential scanning calorimeter coupled to a Digico Micro 16 computer which acted as a data logger. The stored DSC output was analysed by computer to determine the heat capacities. The results are compared with the literature values and analysed in terms of our solution enthalpy studies on HMX.