Analysis of the dynamics of liquid aluminium: recurrent relation approach
Analysis of the dynamics of liquid aluminium: recurrent relation approach
复制标题
液态铝的动力学分析：循环关系法
DOI：
--
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
P. Hänggi
中科院分区：
文献类型：
--
作者：
A. Mokshin;R. Yulmetyev;R. Khusnutdinoff;P. Hänggi
利用循环关系法（RRA）研究了T = 973 K时铝液的微观动力学，建立了一个满足所有相应求和规则的理论模型。研究涵盖了非弹性特征以及我们的理论与流体力学和自由粒子体系的交叉。并将我们的理论结果与广义流体力学方法的结果进行了比较。除此之外，我们还报告了我们对液态铝的分子动力学模拟的结果，并与实验数据进行了讨论和比较。结果表明：(1)密度波动的微观动力学主要由动力结构因子的前四个偶数频率矩来定义；(2)在动力结构因子S（k,ω）的实验光谱中观察到的高频集体激励与二、三、四粒子相关的内在关系。
By use of the recurrent relation approach (RRA) we study the microscopic dynamics of liquid aluminium at T = 973 K and develop a theoretical model which satisfies all the corresponding sum rules. The investigation covers the inelastic features as well as the crossover of our theory into the hydrodynamical and the free-particle regimes. A comparison between our theoretical results with those following from a generalized hydrodynamical approach is also presented. In addition to this we report the results of our molecular dynamics simulations for liquid aluminium, which are also discussed and compared to experimental data. The results obtained reveal (i) that the microscopical dynamics of density fluctuations is defined mainly by the first four even frequency moments of the dynamic structure factor, and (ii) the inherent relation of the high-frequency collective excitations observed in experimental spectra of dynamic structure factor S(k,ω) with the two-, three- and four-particle correlations.