共查询到18条相似文献,搜索用时 125 毫秒
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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) 总被引:1,自引:1,他引:0
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. 相似文献
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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. 相似文献
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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. 相似文献
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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。 相似文献
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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. 相似文献
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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 相似文献
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Darryl Letter 《International Journal of Theoretical Physics》1973,7(3):199-203
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. 相似文献
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《Solid State Communications》1987,62(2):65-68
The electronic structure and atomic relaxation of twin stacking faults along [111] direction in silicon are studied within the local density approximation with first principle cluster model self-consistent calculations. The atomic relaxation obtained from the view point of total energy is in agreement with experiments. The electronic structure, defect levels, and fault energy of twin stacking faults in silicon are also discussed. 相似文献
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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. 相似文献
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-.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。 相似文献
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G. Zwicknagl 《Zeitschrift für Physik B Condensed Matter》1980,40(1-2):23-29
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. 相似文献
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G. Zwicknagl 《Zeitschrift für Physik B Condensed Matter》1980,40(1):23-29
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. 相似文献
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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. 相似文献