物理化学学报 >> 2001, Vol. 17 >> Issue (10): 913-917.doi: 10.3866/PKU.WHXB20011010

研究论文 上一篇    下一篇

锆钴合金氢化反应热力学函数的计算

罗德礼;蒋刚;朱正和;蒙大桥;薛卫东   

  1. 四川大学<西区>原子与分子物理所,成都 610065;中国工程物理研究院,绵阳 621900
  • 收稿日期:2001-04-27 修回日期:2001-06-28 发布日期:2001-10-15
  • 通讯作者: 蒋刚 E-mail:gjiang@pridns.scu.edu.cn

Ab initio of the Thermodynamic Function for the Hydrogenating of Zirconium-Cobalt Alloy

Luo De-Li;Jiang Gang;Zhu Zheng-He;Meng Da-Qiao;Xue Wei-Dong   

  1. Institute of Atomic and Molecular Physics,Sichuan University,Chengdu 610065;China Academy of Engineering Physics,Mianyang 621900
  • Received:2001-04-27 Revised:2001-06-28 Published:2001-10-15
  • Contact: Jiang Gang E-mail:gjiang@pridns.scu.edu.cn

摘要: 在有效原子实势近似下,采用Gaussian 98计算程序及B3LYP/SDD密度泛函方法计算得到了ZrCo和ZrCoH分子的结构、力常数、离解能,能量(E)、熵(S)以及ZrCo与氢同位素气体反应的热力学函数.在固态ZrCo、ZrCoH(D、T)的E和S的计算中,近似以气态分子总能量中的振动能EV代替该分子处于固态时的振动能量,以电子运动和振动运动熵SEv代替分子处于固态的熵,在这种近似下,计算了不同温度下ZrCo与H2、D2、T2反应的ΔH、ΔG、ΔS及氢化反应平衡压力,导出了氢化反应温度与平衡压力的依赖关系.计算得出:ZrCoH、ZrCoD、ZrCoT的生成焓(398~598 K)分别为82.81、81.54和80.49 kJ•mol-1,与实验结果有很好的一致性,表明这种近似处理方法是合理的,可以用于一些未知氢化物的热力学函数的近似计算.

关键词: ZrCo, ZrCoH, 分子结构, 热力学函数, 从头计算

Abstract: Density functional (B3LYP/SDD) method with relativistic effective core potential (RECP) have been used to optimize the structure of ZrCo and ZrCoH,and to calculate energy E,entropy S and enthalpy H of ZrCoH(D,T).Considering the characteristics of different motion types,the vibration energy or electronic and vibration entropy of the molecules is assumed to be the corresponding values of their solid states.ΔH,ΔS,ΔG and hydrogen isotope equilibrium pressures of the hydrogenating reactions have been calculated based on this approximation.The formation enthalpies for ZrCoH,ZrCoD and ZrCoT at temperature from 398 to 598 K are 82.81 ,81.54 and 80.49 kJ•mol-1 respectively.The results cohere with the experimental results.It means that the present method is somehow reasonable to theoretical study on thermodynamic functions of hydrogen storage materials.

Key words: ZrCo, ZrCoH, Molecule structure, Thermodynamic function, Ab initio