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51.
We describe the conformation and stereospecific 1H and 13C chemical shift assignments of longifolene 1 and its penultimate precursor 2 through the combined use of ab initio calculations and experimental NMR techniques. The predicted stable conformation for both compounds was similar and adopts a twisted chair conformation at the seven-membered ring where C4 lies on top of the exocyclic double bond. The calculated chemical shifts for the stable conformation agree well with the experimental values. 相似文献
52.
53.
Miao Changxing Xu Guixiang Zhao Lifeng 《偏微分方程(英文版)》2008,21(1):22-44
In this paper, we systematically study the wellposedness, illposedness of the Hartree equation, and obtain the sharp local wellposedness, the global existence in Hs, s≥1 and the small scattering result in Hs for 2 〈γ〈 n and s ≥ 2/γ - 1. In addition, we study the nonexistence of nontrivial asymptotically free solutions of the Hartree equation. 相似文献
54.
用 FF/PM3 ,FF/AM1 ,CPHF/PM3方法 ,对 N -氧化吡啶及其— NH2 ,— NO2 单双取代衍生物体系的非线性光学性质进行了理论研究 .结果表明 ,这类化合物具有很好的非线性光学性质 ,其中 2 -NH2 -5-NO2 -Py-1 -O和 2 -NH2 -4 -NO2 -Py-1 -O的二阶非线性光学系数均很大 ,而 2 -NH2 -5-NO2 -Py-1 -O三阶非线性光学系数最大 ,且略大于 1 -NH2 -4 -NO2 -Ph 相似文献
55.
H. Sasaki 《Journal of Mathematical Analysis and Applications》2005,309(1):294-306
We shall consider the inverse scattering problem for time dependent version of Hartree equation and nonlinear Klein-Gordon equation. The uniqueness theorem on identifying the cubic convolution nonlinearity from the knowledge of the scattering operator will be shown. 相似文献
56.
Modified transport equations are derived from Kadanoff and Baym kinetic equations, suitable for the study of thermal transport
coefficients. These equations include the Hartree average energy term which has been ignored in the previous studies of thermal
transport coefficients. They are linearised and the successive perturbation method is employed to solve them. The solutions
are applied to shear viscosity coefficient of gases and the results are compared with the recent experimental measurements
for several complex and simple gases. The potential assumed is a hard core one with a perturbation tail. The agreements are
particularly good for gases with low molecular weight and in the high temperature range. For complex molecules even in the
low temperature range, the agreement is better than the previous calculations. The formula derived yields the explicit temperature
dependence of the viscosity coefficient. 相似文献
57.
58.
使用相对论Thomas-Fermi(RTF)及相对论Hartree近似方法,在改进的标量微分耦合模型的基础上,计算了半无穷上核物质中张量耦合及m。的变化对核表面性质与自旋-轨道耦合势的影响.结果表明张量耦合改善了标量微分耦合模型的自旋-轨道耦合势,但核表面张力系数及核表面厚度因张量耦合常数的增加而变小。 相似文献
59.
该文讨论了一类在量子理论中有着较多应用的具耗散项的非线性Hartree方程。分别从耗散系数和初值两个方面讨论了解的整体存在性条件。一方面,利用Strichartz估计,得到仅依赖于耗散系数的整体存在性条件。另一方面,也得到了仅依赖于初值大小的整体存在性条件。而且,还得到了一个整体解存在的小初值准则。 相似文献
60.
Shi‐Lin Hu Zeng‐Xiu Zhao Ting‐Yun Shi 《International journal of quantum chemistry》2014,114(7):441-448
We introduce one‐center method in spherical coordinates to carry out Hartree–Fock calculations. Both the radial wave function and the angular wave function are expanded by B‐splines to deal with electron‐nucleus cusps, which results in the improved convergence for several typical closed‐shell diatomic molecules with moderate basis numbers. B‐splines could represent both the bound state and continuum state wave functions properly, and the present approach has been applied to investigate the ionization dynamics for H2 in the intense laser field adopting single‐active‐electron model. © 2013 Wiley Periodicals, Inc. 相似文献