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A novel compound-monohydrated zinc nicotinate was prepared via room temperature solid phase synthesis and ball grinding.FTIR,chemical and elemental analyses and X-ray powder diffraction technique were applied to characterizing the structure and composition of the complex.Low-temperature heat capacities of the solid coordination compound were measured by a precision automated adiabatic calorimeter over a temperature range from 77 to 400 K.A solid-solid phase transition process occurred in a temperature range of 321―342 K inferred according to the heat capacity curve,and the peak temperature,molar enthalpy and entropy of the phase transition of monohydrated zinc nicotinate were determined to be Ttrs=(340.584±0.829) K,ΔtrsHm=(12.682±0.041) kJ/mol and ΔtrsSm=(37.235±0.101) KJ/mol).The experimental values of the molar heat capacities in the temperature regions of 77―321 K and 342―400 K were,respectively,fitted to two polynomial equations.In addition,the polynomial fitted values of the molar heat capacities and fundamental thermodynamic functions of the sample relative to the standard reference temperature 298.15 K were calculated and tabulated at intervals of 5 K.
A novel compound-monohydrated zinc nicotinate was prepared via room temperature solid phase synthesis and ball grinding. FTIR, chemical and elemental analyzes and X-ray powder diffraction technique were applied to characterizing the structure and composition of the complex. Low-temperature heat capacities of the solid coordination compound were measured by a precision automated adiabatic calorimeter over a temperature range from 77 to 400 KA solid-solid phase transition process in a temperature range of 321-342 K inferred according to the heat capacity curve, and the peak temperature, molar enthalpy and entropy of the phase transition of monohydrated zinc nicotinate were determined to be Ttrs = (340.584 ± 0.829) K, ΔtrsHm = (12.682 ± 0.041) kJ / mol and ΔtrsSm = (37.235 ± 0.101) KJ / mol) values of the molar heat capacities in the temperature regions of 77-321 K and 342-400 K were, respectively, fitted to two polynomial equations. In addition, the polynomial fitted values o f the molar heat capacities and fundamental thermodynamic functions of the sample relative to the standard reference temperature 298.15 K were calculated and tabulated at intervals of 5 K.