Synthesis, Characterization and Thermochemistry of the Hydrated Barium Nicotinate
Synthesis, Characterization and Thermochemistry of the Hydrated Barium Nicotinate
复制标题
水合烟酸钡的合成、表征及热化学
DOI：
10.3866/pku.whxb20081025
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发表时间：
2008-10
影响因子：
10.9
通讯作者：
Shi Quan
中科院分区：
文献类型：
--
作者：
Di You-Ying;Kong Yu-Xia;Yang Wei-Wei;Zhang Shuang;Tan Zhi-Cheng;Wu En-Shen;Shi Quan
一种新化合物。三水合烟酸钡，通过室温固相合成法和球磨法合成。采用红外光谱、化学分析、元素分析和X射线粉末衍射等技术对配合物的结构和组成进行了表征。用精密自动绝热量热计测定了该配合物在78 ~ 400 K温度范围内的低温热容。热容曲线在312-332 K范围内发生了相变过程，确定了该配合物固-固相变的峰温、摩尔焓和摩尔熵为：T-trs=（327.097+/-1.082）K，Δ H-trs（m）=（16.793+/-0.084）kJ中心点mol（-1）和Δ S-trs（m）=（51.340+/-0.164）J中心点K-1中心点mol（-1）。将78 -311 K和333-400 K温度范围内摩尔热容的实验值分别拟合为两个多项式方程。计算了样品相对于标准参考温度298.15K的摩尔热容和基本热力学函数的多项式拟合值，并以5 K为间隔制表。根据Hess定律设计了热化学循环，确定了固相反应的反应焓Δ H-t（m）0 =-（84.12+/-0.38）kJ中心点mol（-1），并将络合物的标准摩尔生成焓计算为Δ H-f（m）0 [Ba（Nic）（2）中心点3 H（2）O（s）]=-（2115.13 ± 1.90）kJ中心点mol（-1）。
A new compound. barium nicotinate trihydrate, wits synthesized by the method of room temperature solid phase synthesis and ball grinder. FTIR, chemical and elemental analyses, and X-ray powder diffraction techniques were applied to characterize the structure and composition of the complex. Low-temperature heat capacities of the solid coordination compound were measured by it precision automated adiabatic calorimeter over the temperature range from 78 to 400 K. A phase transition process occurred in the temperature range of 312-332 K in the heat capacity curve, and the peak temperature, molar enthalpy and entropy of the solid-to-solid phase transition of the complex were determined to be its follows: T-trs=(327.097+/-1.082) K, Delta H-trs(m)=(16.793+/-0.084) kJ center dot mol(-1) and Delta S-trs(m) =(51.340+/- 0.164) J center dot K-1 center dot mol(-1). The experimental values of the molar heat capacities in the temperature regions of 7 8-311 K and 333-400 K were respectively fitted to two polynomial equations. The polynomial fitted values of the molar heat capacities and fundamental thermodynamic functions of the sample relative to the standard reference temperature of 298.15 K were calculated and tabulated at an interval of 5 K. In accordance with Hess law, it thermochemical cycle was designed, the reaction enthalpy of the solid phase reaction was determined its Delta H-t(m)0 =-(84.12+/-0.38) kJ center dot mol(-1), and the standard molar enthalpy of formation of the complex was calculated as Delta H-f(m)0 [Ba(Nic)(2) center dot 3H(2)O(s)]=-(2115.13+/-1.90) kJ center dot mol(-1) by using an isoperibol solution-reaction calorimeter.
DOI：
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发表时间：
1989
期刊：
--
影响因子：
--
作者：
J. Cox;D. Wagman;V. Medvedev
通讯作者：
J. Cox;D. Wagman;V. Medvedev