Crystal Structure and Solid–Solid Phase Transition of 1-Dodecylamine Hydrobromide

Abstract

Abstract 1-dodecylamine hydrobromide was synthesized. The crystal structure of the compound was determined by X-ray crystallography. Low-temperature heat capacities of the title compound were measured by an adiabatic calorimeter over the temperature range from 78 to 390 K. Three solid–solid phase transitions were observed at the peak temperatures of (329.278±0.234), (337.805±0.326), and (347.371±0.154) K. The molar enthalpies and entropies of the three phase transitions of the substance were calculated based on the analysis of heat capacity curves. Experimental values of heat capacities for the title compound were fitted to two polynomial equations. Three solid–solid phase transitions and a melting process of 1-dodecylamine hydrobromide were verified by DSC technique. In addition, the reversibility and repeatability of the three phase transitions were discussed.