2-氯-N,N-二甲基尼古丁酰胺的热容和热力学性质研究

Low-temperature heat capacities of 2-chloro-N,N-dimethylnicotinamide were precisely measured with a high-precision automated adiabatic calorimeter over the temperature range from 82 K to 380 K. The compound was observed to melt at （342.15±0.04） K. The molar enthalpy AfusionHm, and entropy of fusion, △fusionSm, as well as the chemical purity of the compound were determined to be （21387±7） J·mol^-1, （62.51±0.01） J·mol^-1·K^-1, （0.9946±0.0005） mass fraction, respectively. The extrapolated melting temperature for the pure compound obtained from fractional melting experiments was （342.25±0.024） K. The thermodynamic function data relative to the reference temperature 298.15 K were calculated based on the heat capacity measurements in the temperature range from 82 to 325 K. The thermal behavior of the compound was also investigated by different scanning calorimetry.

Heat Capacity and Thermodynamic Properties of Crystalline 2-Chloro- N, N-dimethylnicotinamide

Low‐temperature heat capacities of 2‐chloro‐N,N‐dimethylnicotinamide were precisely measured with a high‐precision automated adiabatic calorimeter over the temperature range from 82 K to 380 K. The compoundwas observed to melt at (342.15±0.04) K. The molar enthalpy Δ_fusionH_m, and entropy of fusion, Δ_fusionS_m, as well as the chemical purity of the compound were determined to be (21387±7) J·mol^?1, (62.51±0.01) J·mol^?1·K^?1, (0.9946±0.0005) mass fraction, respectively. The extrapolated melting temperature for the pure compound obtained from fractional melting experiments was (342.25±0.024) K. The thermodynamic function data relative to the reference temperature 298.15 K were calculated based on the heat capacity measurements in the temperature range from 82 to 325 K. The thermal behavior of the compound was also investigated by different scanning calorimetry.