Thermal energy of the crystalline one-component plasma from dynamical simulations.
Thermal energy of the crystalline one-component plasma from dynamical simulations.
复制标题
动力学模拟中结晶单组分等离子体的热能。
DOI：
10.1103/physreve.47.4330
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Hamaguchi
中科院分区：
文献类型：
--
作者：
Farouki;Hamaguchi
采用1024个粒子的分子动力学模拟和高精度的Ewald势样条近似，在很大的耦合参数范围内(1[LE][Gamma][LE]2000)测量了经典单组分等离子体在流体和固体(Bcc)相中的超额内能。[Gamma][LE]300的能量数据与以前的蒙特卡罗计算在这个范围内很好地吻合，给出了这些计算的独立佐证。用170[LE][GAMMA][LE]2000晶区的数据，通过最小二乘拟合法估计了非简谐能量分量的系数。第一个系数与摄动理论的预测是合理一致的，尽管有人认为以这种方式确定系数是一个相当病态的问题。发现流体和固体相的自由能曲线在[Gamma][sub[italm]][约]173处交叉，这与最近的估计一致。
Molecular-dynamics simulations employing 1024 particles and a high-accuracy spline approximation of the Ewald potential have been used to measure the excess internal energy of the classical one-component plasma in both the fluid and solid (bcc) phases over a wide range (1[le][Gamma][le]2000) of the coupling parameter. The energy data for [Gamma][le]300 are in excellent agreement with previous Monte Carlo calculations for this range, giving an independent corroboration of these calculations. Data in the crystalline regime 170[le][Gamma][le]2000 are used to estimate the coefficients of the anharmonic energy component by least-squares fits. The first coefficient is in reasonable agreement with peturbation-theory predictions, although it is argued that determination of the coefficients in this manner is a rather ill-conditioned problem. The free-energy curves of the fluid and solid phases are found to cross at [Gamma][sub [ital m]][approx]173, in agreement with recent estimates.