改进的含温有界原子模型对金的电子物态方程的计算

在改进的含温有界原子模型基础上,在中心场近似下用分波法来处理部分自由电子密度分布函数.通过平均近似处理,给出劈裂的能带.在原子结构的自洽计算中采用能带重叠作为自由电子的动态判据.大量计算了Au的电子压强、能量、热容以及各种热力学系数. 关键词： 自洽场原子结构 状态方程 原子能量 电子压强     

利用不同原子模型计算局部热力学平衡等离子体电离态(英文)

等离子体电离态分布是等离子体物理学中被广泛应用的重要物理量之一,而原子数据是电离态计算的前提.首先,利用Rubiano相对论性原子结构模型、Faussurier非相对论原子结构模型和高度简化的More模型,分别计算各种电离度的Fe离子能量.通过与自洽场结果的比较后认为,Faussurier模型给出的原子数据比较精确可靠.然后,再利用以上模型研究了局部热力学平衡Fe等离子体电离态随温度和密度的变化情况.计算结果表明,不同原子模型提供的原子数据对平均电离度的计算结果影响不大,但明显地影响等离子体中的离子丰度.本文对这些差异进行了物理分析.     

在二维原子自洽场计算中的Gaussian函数展开方法

报告了在二维原子结构的自洽场计算中,单电子波函数向笛卡尔Gaussian函数展开的基本方法.推导了由s,p和d电子组成的闭壳层和开壳层电子组态的能量表达式,和二维的Hartree-Fock-Roothaan HFR方程,最后给出了二维原子自洽场计算的主要结果精度的讨论.     

Pb等离子体电子压强的自洽场计算

对含温有界自洽场平均原子结构中,用分波法和Fermi-Dirac统计处理自由电子.在计算电子压强时考虑了共振态和交换、库仑关联对压强的影响.以Pb为算例,计算了Pb在一些温度密度点下的电子压强,并将计算结果与TF、TFD(Thomas-Fermi-Dirac)等模型作了比较.     

快速计算细致组态原子结构

细致组态原子结构模型一般适用于高温低密度等离子体。细致组态原子结构模型将有界自洽场原子结构模型与Saha方程耦合在一起，考虑自由电子背景对束缚电子能级的影响，通过自洽迭代达到离子结构计算自洽和等离子体自由电子背景自洽。该模型对较大温度密度范围内的等离子体适用，然而在一定的温度密度范围内，等离子体内存在的组态很多，细致组态原子结构难以计算。这使得该模型难以应用到离子组态数目巨大的重元素上去。为此文章通过合并组态来快速计算等离子体细致组态原子结构，避免人为的丢掉部分高激发组态从而丢失一定的精度，并为将HFSBS方法应用到中、重元素开辟一条可能的途径。     

用Hartree-Fock-Slater-Boltzmann-Saha模型研究等离子体细致组态原子结构及其状态方程

用平均原子自洽势计算等离子体的自由电子背景,通过在Hartree-Fock-Slater自洽场原子结构中引入背景修正计算离子组态结构,为Boltzmann-Saha方程提供能级参数,再通过调节共同的背景电子实现Saha方程与Hartree-Fock-Slater方程的耦合,自洽求解等离子体细致组态原子结构,提高Saha方程的计算精度.以碳、铝等离子体作为算例,分析了本方法的适用范围.     

用Hartree-Fock-Slater-Boltzmann-Saha模型研究等离子体细致组态原子结构及其状态方程

用平均原子自洽势计算等离子体的自由电子背景，通过在Hartree Fock Slater自洽场原子结构中引入背景修正计算离子组态结构，为Boltzmann Saha方程提供能级参数，再通过调节共同的背景电子实现Saha方程与Hartree Fock Slater方程的耦合，自洽求解等离子体细致组态原子结构，提高Saha方程的计算精度.以碳、铝等离子体作为算例，分析了本方法的适用范围. 关键词： 原子结构 Boltzman Saha方程 状态方程     

包含过渡区的等离子体电子状态方程的理论研究

在改进的平均原子模型的基础上,在中心场近似下用分波法来处理部分自由电子密度分布函数,提高了电子波函数、电子占据数等原子参数的计算精度.通过平均近似处理,给出了劈裂的能带,从而改善了物质电子状态方程的计算精度.作为算例,计算了Mo,Au等元素的原子能量、电子压强、熵及定容热容. 关键词： 自洽场原子结构 原子能量     

中低温稠密等离子体电子压强的自洽场计算

 对含温有界自洽场平均原子结构中自由电子的判据作了修改,用分波法和Fermi-Dirac统计处理自由电子。在计算电子压强时考虑了共振态和交换、库仑关联对压强的影响。计算并与实验比较了Ni、Cu的零温电子压强。以Fe、Pb为算例,展示了本模型的适用性。     

离子组态效应对电子传导不透明度的影响

基于相对论Hartree-Fock-Slater 自洽场原子结构模型, 考虑电子-离子间的弹性散射机制, 用分波法和扩展的Ziman 公式对电子传导不透明度作了计算。考虑到等离子体离子环境的影响, 不仅引进了等离子体的结构因子, 而且更细致地考虑了等离子体内离子类型 (组态) 对电子传导     

Difficulties inherent in Sach's new theory of elementary matter

We show that the atomic energy levels, predicted by a recently proposed new theory of elementary matter, are in one-to-one correspondence with the relativistic Hartre self-consistent field theory for atomic structure. This means that this theory will contain solutions which violate the Pauli Exclusion Principle, as well as neglect the important effects of Configuration Interaction in atomic structure. This would tend to cast doubt on the viability of the new theory in its present form.     

Self-consistent calculation of the band structure of copper by the LMTO method

Conclusion In our paper we have presented an effective self-consistent procedure which has been applied to the calculation of the electronic structure of copper. The results attest to the high stability of this procedure. The method of previously attaining atomic self-consistency makes possible a substantial reduction of the volume of band-structure calculations and, therefore, of the total time of the SC procedure. It has thus become possible to carry out calculations with good accuracy for a number of physical properties and the binding energy of metals on medium-sized computers. It must be pointed out that the self-consistent calculation of the band structure with prior attainment of atomic self-consistency is also possible in other methods of constructing the band structure.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 103–107, July, 1983.The authors are grateful to Yu. Kh. Velikov and E. G. Maksimov for their attention and advice.     

关於分子结構的一个新的量子力学计算方法

-.引言 量子化学方法在解决化学结构问题上应该起很大作用。切列宁院士1951年在有机化学中化学结构理论问题的全苏联讨论会上指出,为进一步发展分子结构理论,必须创造新的更完善的量子力学计算方法。     

The influence of short-range order on electronic properties of transition metals: I. Crystalline systems

Densities of states and electronic parameters related to superconductivity have been calculated for the transition metals Nb and Tc, representing the bulk materials by a finite cluster of atoms. The Schrödinger equation is solved for atomic potentials which have been obtained in a self-consistent band structure calculation. The results show that, in these systems, the electronic structure is determind predominantly by short-range order.     

The influence of short-range order on electronic properties of transition metals: I. Crystalline systems

Densities of states and electronic parameters related to superconductivity have been calculated for the transition metals Nb and Tc, representing the bulk materials by a finite cluster of atoms. The Schrödinger equation is solved for atomic potentials which have been obtained in a self-consistent band structure calculation. The results show that, in these systems, the electronic structure is determind predominantly by short-range order.     

Effect of chromium on the electronic structure of the cementite Fe3C

The effect of alloying of the cementite Fe₃C with chromium on the band structure, atomic interactions, electric field gradients, and asymmetry parameters for iron nuclei is investigated using the self-consistent full-potential linear muffin-tin orbital (FPLMTO) method. An increase in the cohesive energy for the Fe₃C-Cr system indicates an enhancement of the atomic interactions in the lattice of the cementite alloyed with chromium. It is found that the substitution of chromium for iron in the FeII positions containing eight equivalent iron atoms is energetically most favorable.     

Calculated angular dependence of the interlayer couplings in Fe/Cr superlattices having imperfect interfaces

We present calculations of the non-collinear magnetic structure in Fe/Cr superlattices having imperfect interfaces modeled by considering atomic steps in the Cr layers and Fe/Cr interfacial ordered compounds. The interlayer couplings are obtained directly from self-consistent tight binding band structure calculations. We show that the bilinear–biquadratic expression for the coupling energy fits nicely the calculated interlayer couplings curves.