【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 .更多还原

【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.更多还原