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101.
We describe rigorously a many-body model of interacting classical particles exhibiting the following behavior at zero temperature: as the pressure varies through a critical value, the system goes through a first-order phase transition between different crystal phases. Moreover, at the critical pressure the system is demonstrably a mixture of the two phases.Supported in part by NSF Grant No. MCS81-01596. 相似文献
102.
ZOU Wen-Hua TIAN Yuan SHEN Shui-Fa GU Jian-Zhong PENG Bang-Bao ZHANG Di-Da MA Zhong-Yu 《中国物理C(英文版)》2010,34(1)
Recent years have witnessed intense activity concerning the study of nuclei with equal numbers of neutrons and protons (N = Z). Exotic properties have been exhibited in the N = Z nuclei, especially in those with atomic masses around 80. In the present paper, the projected shell model(PSM)together with a relativistic Hartree-Bogoliubov (RHB) theory is used to study the nuclear structure near the N = Z line in the mass A ≈ 80 region. For three Zr isotopes 80,82,84Zr, the projected potential energy surfaces and ground state bands are calculated. It is shown that shape coexistence occurs in all of these nuclei. Moreover, we find that the residual neutron-proton interaction strongly affects the ground state band of 80Zr; however, it slightly modifies those of 82Zr and 84Zr. 相似文献
103.
The possible geometrical and the electronic structures of small MgnNi(n = 1-7) clusters are optimised by the density functional theory with a LANL2DZ basis set.The binding energy,the energy gap,the electron affinity,the dissociation energy and the second difference in energy are calculated and discussed.The properties of Mg n Ni clusters are also discussed when the number of Mg atom increases. 相似文献
104.
采用密度泛函的B3P86方法,以6-311+G(3df)为基函数优化得到不同外电场下FO基态分子的稳定几何结构、键长、总能量、HOMO能级、LUMO能级、费米能级、能隙、红外光谱和谐振频率.结果表明,分子结构与外电场有着强烈的依赖关系,且对电场方向的依赖呈现出不对称性;随着正向电场的增大,HOMO能级、LUMO能级和费米能级是减小的,能隙是先增大后减小;红外光谱和谐振频率是增大的,而频率间隔是不断减小的. 相似文献
105.
《Mathematical Methods in the Applied Sciences》2018,41(1):317-335
This paper is focused on following time‐harmonic Maxwell equation: where is a bounded Lipschitz domain, is the exterior normal, and ω is the frequency. The boundary condition holds when Ω is surrounded by a perfect conductor. Assuming that f is asymptotically linear as , we study the above equation by improving the generalized Nehari manifold method. For an anisotropic material with magnetic permeability tensor and permittivity tensor , ground state solutions are established in this paper. Applying the principle of symmetric criticality, we find 2 types of solutions with cylindrical symmetries in particular for the uniaxial material. 相似文献
106.
Existence of ground state solutions for Kirchhoff‐type problems involving critical Sobolev exponents
《Mathematical Methods in the Applied Sciences》2018,41(1):371-385
In this paper, we study the existence of ground state solutions for a Kirchhoff‐type problem in involving critical Sobolev exponent. With the help of Nehari manifold and the concentration‐compactness principle, we prove that problem admits at least one ground state solution. 相似文献
107.
This paper is concerned with the existence and asymptotical behavior of positive ground state solutions for a class of critical quasilinear Schrodinger equation.By using a change of variables and variational argument,we prove the existence of positive ground state solution and discuss their asymptotical behavior。 相似文献
108.
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110.
考虑一个特殊的非线性奇偶对称模型,研究相关的基态光学模式,并通过功率和复折射率虚部的振幅之间的依赖关系来直观地判断光学模式的稳定性,这对理解和掌握奇偶对称复折射率分布波导中的光传输特性具有非常重要的实际意义. 相似文献