物理化学学报 >> 2001, Vol. 17 >> Issue (05): 416-421.doi: 10.3866/PKU.WHXB20010508

研究论文 上一篇    下一篇

链状分子状态方程的推导及热容的推算

梁世强;张秉坚;路映红;胡文暄;金之钧   

  1. 浙江大学化学系,杭州 310027;南京大学地球科学系,南京 210093;石油大学盆地与油藏研究中心,北京 102200
  • 收稿日期:2000-09-21 修回日期:2000-12-19 发布日期:2001-05-15
  • 通讯作者: 张秉坚 E-mail:zbj@mail.hz.zj.cn

New Perturbation Theory Model for Chainlike Molecule Fluid and the Predicted Heat Capacity

Liang Shi-Qiang;Zhang Bing-Jian;Lu Ying-Hong;Hu Wen-Xuan;Jin Zhi-Jun   

  1. Department of Chemistry,Zhejiang University,Hangzhou 310027;Department of Earth Sciences,Nanjing University,Nanjing 210093;Basin and Reservoir Research Center,China Petroleum University,Beijing 102200
  • Received:2000-09-21 Revised:2000-12-19 Published:2001-05-15
  • Contact: Zhang Bing-Jian E-mail:zbj@mail.hz.zj.cn

摘要: 在BarkerHenderson, Zhang以及Wertheim 等微扰理论的基础上,以方阱势硬球流体为参考体系,将Zhang的解析表达方法与Wertheim 的链成键自由能的处理方法结合起来,推导出自由链接的链状分子流体的Helmholtz自由能的解析表达式,并得到了压缩因子、内能、恒容热容等热力学性质的计算式.计算结果与MC(Monte Carlo)模拟结果吻合良好.对Zhang的解析表达式与“TPTD”(二阶Wertheim微扰理论)的结合也作了推导和计算.

关键词: 链分子, 方阱势, 微扰理论, 热力学性质, MC模拟

Abstract: A model for the freely jointed square well chain fluid is developed based on the thermodynamic perturbation theory of BarkerHenderson,Zhang and Wertheim.The analytic representations of squarewell monomer by Zhang are extended to obtain a series of representations for thermodynamic properties of squarewell chain fluids using the incorporating structural information for squarewell monomer of Wertheim's TPT1 model.The same work has been done using incorporating structural information for the diatomic squarewell fluid of TPTD model.The calculated results of compressibility factor,residual internal energy and constantvolume heat capacity of 4mer,8mer and 16mer chain fluids are tested against the MC results and a careful comparison between the model from TPT1 and that from TPTD has been made.The former agree with MC results much better than the later,especially for internal energy.To obtain the constantvolume heat capacity,NVT MC simulations have been performed.

Key words: Chain-like molecule, Square-well potential, Perturbation theory,  Thermodynamic property, Monte Carlo simulation