Ushcats M V
National University of Shipbuilding, Geroyev Stalingrada avenue 9, Mykolayiv 54025, Ukraine.
J Chem Phys. 2014 Sep 14;141(10):101103. doi: 10.1063/1.4895126.
The regularity of the existing data on the virial coefficients for the Lennard-Jones and modified Lennard-Jones models has allowed a rough extrapolation to the coefficients of higher orders. The corresponding approximation of the infinite virial series has been proposed for the limited temperature interval: 0.4-0.8 of the critical temperature. The loci of zero points of isothermal bulk modulus obtained on the basis of this approximation are close to the vapor-liquid branch of the experimental binodal rather than spinodal. In addition, those points ((dP/dV)T = 0) almost coincide with the divergence points of the approximated virial series that may eliminate some disputable questions about the boundaries of adequacy for the virial equation of state and makes the theoretical isotherms qualitatively similar to the real in the condensation region.
关于 Lennard-Jones 模型和修正的 Lennard-Jones 模型的维里系数的现有数据的规律性，使得可以粗略地外推到更高阶的系数。针对有限的温度区间（临界温度的 0.4 - 0.8），已经提出了无限维里级数的相应近似。基于该近似得到的等温体积模量零点的轨迹更接近实验双节线的气液分支，而非旋节线。此外，那些点（(dP/dV)T = 0）几乎与近似维里级数的发散点重合，这可能消除了关于维里状态方程适用边界的一些有争议的问题，并使理论等温线在冷凝区域与实际等温线在定性上相似。
