Low temperature behavior of thermodynamic perturbation theory.
Low temperature behavior of thermodynamic perturbation theory.
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热力学微扰理论的低温行为。
DOI：
10.1039/b916373e
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发表时间：
2009-12
期刊：
影响因子：
--
通讯作者：
Solana, J R
中科院分区：
文献类型：
--
作者：
Zhou, Shiqi;Solana, J R
用Monte Carlo方法模拟了λ = 1.01，1.02和1.04的硬球方阱模型流体的压力、过剩亥姆霍兹自由能和内能、定容过剩热容、过剩化学势和过剩焓等热力学性质。考虑到极窄的阱宽，我们可以在极低的温度下进行模拟，而不会达到液体-蒸气转变，这对于这些λ值是亚稳态的。这些模拟数据已被用来探讨两个热力学微扰理论（TPT）的低温行为，即在局部压缩性近似下在二阶截断的高温级数展开（下文表示为二阶LCA-TPT）和最近提出的在三阶、四阶和五阶截断的耦合参数级数展开（此后分别表示为3阶、4阶和5阶TPT）。已经发现，二阶LCA-TPT是定性不正确的，在大多数情况下分析，而三阶TPT是定量正确的，在大多数情况下。随着阱宽的增加，以及因此考虑的温度的增加，三阶TPT迅速变得更准确。在分析的六个热力学量中，最难准确预测的是定容过剩热容，基于耦合参数展开的TPT仅在λ = 1.04的情况下提供了令人满意的结果。对于所研究的情况下，性能的第三阶，第四阶，和第五阶TPT基本上是相等的，截断的顺序的变化有时会导致在某些区域内的热力学表面的状态，而在其他恶化的一些热力学量的改善。
Monte Carlo simulations have been carried out for a hard sphere square well model fluid with well widths of lambda = 1.01, 1.02 and 1.04 to obtain thermodynamic properties, such as pressure, excess Helmholtz free energy and internal energy, constant volume excess heat capacity, excess chemical potential, and excess enthalpy. The extremely narrow well widths considered allowed us to perform simulations at extremely low temperatures without reaching the liquid-vapour transition, which is metastable for these values of lambda. These simulation data have been used to explore the low temperature behavior of two thermodynamic perturbation theories (TPT), namely a high temperature series expansion truncated at second order within the local compressibility approximation (thereafter denoted as 2nd-order LCA-TPT) and a recently proposed coupling parameter series expansion truncated at 3rd-, 4th- and 5th-order (thereafter denoted as 3rd-order, 4th-order and 5th-order TPT, respectively). It has been found that the 2nd-order LCA-TPT is qualitatively incorrect in most of the cases analyzed, whereas the 3rd-order TPT is quantitatively correct in most of them. With increasing the well width, and consequently the temperatures considered, the 3rd-order TPT quickly becomes more accurate. Among the six thermodynamic quantities analyzed, the one most difficult to predict accurately is the constant volume excess heat capacity, for which the TPT based on the coupling parameter expansion provides satisfactory results only in the case of lambda = 1.04. For the cases studied, the performance of the 3rd-order, 4th-order, and 5th-order TPT are essentially equal; the change of the order of the truncation sometimes results in an improvement of some thermodynamic quantities within certain regions of the thermodynamic surface of states, while worsening in others.
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DOI：
10.1103/physreve.74.051504
发表时间：
2006-10
期刊：
Physical review. E, Statistical, nonlinear, and soft matter physics
影响因子：
--
作者：
M. Sztucki;T. Narayanan;G. Belina;A. Moussaïd;Frédéric Pignon;H. Hoekstra
通讯作者：
M. Sztucki;T. Narayanan;G. Belina;A. Moussaïd;Frédéric Pignon;H. Hoekstra
DOI：
10.1103/physreve.48.4599
发表时间：
1993-12
期刊：
Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics
影响因子：
--
作者：
Yuste;Santos
通讯作者：
Yuste;Santos
DOI：
10.1103/physreve.78.026415
发表时间：
2008-08
期刊：
Physical review. E, Statistical, nonlinear, and soft matter physics
影响因子：
--
作者：
Yan Feng;Bin Liu;J. Goree
通讯作者：
Yan Feng;Bin Liu;J. Goree
影响因子：
4.4
作者：
CARNAHAN, NF;STARLING, KE
通讯作者：
STARLING, KE
影响因子：
1.7
作者：
Farzad Alavi;F. Feyzi
通讯作者：
Farzad Alavi;F. Feyzi