Structure of Some 4f Rare Earth Liquid Metals — A Charged Hard Sphere Approach

A well-established pseodopotential is used to study the structure of some 4f rare earth liquid metals (Ce, Pr, Eu, Gd, Tb, and Yb). The structure factor S(q), pair distribution function g(r), interatomic distance r₁, and coordination number n₁ are calculated using Charged Hard Sphere (CHS) reference system. To introduce the exchange and correlation effects, the local field correction due to Sarkar et al. (S) is applied. The present investigation is successful in generating the structural information of Ce, Pr, Eu, Gd, Tb, and Yb 4f rare earth liquid metals.     

A Global Investigation About Hard Core Attractive Yukawa Approximation and Adhesive Hard Sphere Approximation for Structure of Colloidal Dispersion Systems

The accuracy of hard core attractive Yukawa (HCAY) potential and adhesive hard sphere (AH) potential in representing the structure factor of short range square well potential and Asakura and Oosawa (AO) depletion potential is examined by comparing theoretical predictions with the existing simulation data and the present numerical results from the non-linear optimized random phase approximation closure for Ornstein-Zernike equation. For the case of square-well (SW) potential, it is shown that the structure factor of HCAY potential based on a recently proposed semi-analytical expression for the radial distribution function can describe the structure factor of SW potential with reduced well width λ≤2 only if the reduced contact potential βε_SW≤0.25, while the analytical expression for the structure factor of AH potential under Percus-Yevick (PY) approximation completely fails for the case of λ>1.2. For the case of AO depletion potential, the domain of validity of both HCAY potential and AH potential is complementary. With the above analysis and considering the solid-liquid transition of the AH potential with an adhesive parameter τ below 1.31 cannot be predicted by modified weighted density approximation, the role played by the HCAY potential about the mapping manipulation should not be ignored.     

3d系列 (TM)4 团簇的结构和磁性

基于第一性原理，在密度泛函理论下，用局域自旋密度近似(LSDA)和广义梯度近似(GGA)对(TM)₄团簇的所有几何构型进行优化、能量、频率和磁性计算.确定出3d系列(TM)₄团簇的基态构型，对其磁性、结合能和平均原子间距作了系统的研究，得出在3d系列(TM)₄团簇中，Mn₄的局域磁矩最大，V₄的局域磁矩最小，并且除Cr₄在LSDA和GGA均为反铁磁性耦合及GGA下的V_{关键词： 4}团簇')" href="#">(TM)₄团簇 基态构型 结合能 局域磁矩 平均原子间距