Sesé Luis M
Departamento de Ciencias y Técnicas Fisicoquímicas, Facultad de Ciencias, Universidad Nacional de Educación a Distancia, Paseo Senda del Rey 9, 28040 Madrid, Spain.
J Chem Phys. 2009 Feb 21;130(7):074504. doi: 10.1063/1.3077126.
The pair and triplet structures of the quantum hard-sphere Yukawa fluid, evaluated for equilateral and isosceles correlations in both the r and the k spaces for a range of conditions and with a particular focus on a region where the onset of increasing number fluctuations takes place (for densities 0.4<or=rho(N) ( *)<or=0.5, along the isotherm lambda(B) ( *)=0.6), are computed via path-integral Monte Carlo simulations in the canonical ensemble and an appropriate Ornstein-Zernike framework. For a given type of correlation (instantaneous, continuous linear response, and centroids), the structural results in r space display how the correlation functions approach each other with decreasing densities as a result of the increasing fluctuations. An attempt at obtaining improved isothermal compressibilities by using a simplified grand-canonical correction to the canonical pair radial functions is also discussed in detail. The results for triplets in k space are based on triplet direct correlation function calculations and are restricted to the higher-density region of the interval studied. Complementary results report an assessment of the performances of the Kirkwood superposition and the Jackson-Feenberg convolution. Comparisons with results also obtained in this work for the bare quantum and the classical hard-sphere fluids are made, allowing one to draw conclusions on the interplay between the inclusion of Yukawa attractions and the quantum diffraction effects in hard-sphere fluids.
通过正则系综中的路径积分蒙特卡罗模拟和适当的奥恩斯坦 - 泽尔尼克框架，计算了量子硬球汤川流体的对结构和三重态结构，评估了一系列条件下r空间和k空间中的等边和等腰相关性，并特别关注数量涨落开始增加的区域（对于密度0.4≤ρ(N)()≤0.5，沿着等温线λ(B)() = 0.6）。对于给定类型的相关性（瞬时、连续线性响应和质心），r空间中的结构结果显示了由于涨落增加，相关函数如何随着密度降低而相互接近。还详细讨论了通过对正则对径向函数使用简化的巨正则校正来获得改进的等温压缩率的尝试。k空间中三重态的结果基于三重态直接相关函数计算，并且限于所研究区间的高密度区域。补充结果报告了对柯克伍德叠加和杰克逊 - 芬伯格卷积性能的评估。还与在这项工作中获得的裸量子和经典硬球流体的结果进行了比较，从而能够就汤川吸引力的纳入与硬球流体中的量子衍射效应之间的相互作用得出结论。
