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71.
72.
首先用Huxley势函数形式拟合了在RCCSD(T)/aug-cc-pVTZ+bf理论水平下计算的He-NO相互作用能数据,获得了He原子与NO分子相互作用的各向异性势,然后采用密耦近似方法计算了He-NO碰撞体系的总微分截面、弹性微分截面和非弹性微分截面,并总结了微分散射截面的变化规律. 结果表明,拟合势不但表达形式简洁,而且较好地描述了He-NO系统相互作用的各向异性特征;利用碰撞体系分子间势的量子化学从头计算结果,可解决势能参数难以确定的问题,对进一步研究原子与分子碰撞机理有一定参考价值.
关键词:
各向异性势
势能参数
密耦近似
微分截面 相似文献
73.
The photo-detachment cross section of H^- near two parallel elastic interfaces is derived and calculated by using the closed orbit theory. The photo-detachment cross section of H^- near two interfaces is shown to exhibit multi-periodic oscillations when the distance between the H^- and the interface is varied. Each peak in the Fourier transformed photo-detachment cross section corresponds to the length of a closed orbit, which is quite similar to the case of atomic spontaneous emissions in a dielectric slab. This study provides a new understanding of the photo=detachment process of H^- in the presence of interfaces. 相似文献
74.
《Journal of computational and graphical statistics》2013,22(3):731-752
This article describes a reduction formula for the computation of multivariate normal probabilities first developed by Plackett. The method is recursive and, despite very promising results, seems not to have been implemented before. Extensive numerical results are given to compare the effectiveness of the approach to other methods from the literature. 相似文献
75.
Nidhi Sinha 《Molecular physics》2013,111(18):2527-2534
ABSTRACTThis work aims at the calculation of various inelastic cross sections for three pentane isomers, namely normal pentane, isopentane and neopentane. The direct ionisation, positronium formation, total ionisation and total inelastic cross section are reported for these targets using modified spherical complex optical potential (mSCOP) and complex scattering potential-ionisation contribution (CSP-ic) method. The cross sections are computed for a wide energy range from their respective thresholds to 5?keV. We have also attempted to probe the isomeric effect in the inelastic scattering of positrons from the pentane isomers. The cross sections for the three isomers were found to overlap for the entire comparative energy range except at the peak region. Hence, in general no appreciable isomeric effect was beheld for the pentane isomers. 相似文献
76.
ZnS微粒子的光学截面及红外发射率光谱的计算 总被引:13,自引:1,他引:12
应用微粒子Mie散射理论,计算了ZnS粒子的散射、吸收和消化截面,并计算了相应粒子的红外发射率光谱,讨论了ZnS粒子在4.0-10.0μm红外波段上的振荡吸收现象。 相似文献
77.
The effects of absolute energy calibration on BESⅢ physics are discussed in detail,which mainly involve the effects on τ mass measurement,cross section scan measurement,and generic error determination in other measurements. 相似文献
78.
The rectangular dielectric waveguide is the most commonly used structure in integrated optics, especially in semi-conductor
diode lasers. Demands for new applications such as high-speed data backplanes in integrated electronics, waveguide filters,
optical multiplexers and optical switches are driving technology toward better materials and processing techniques for planar
waveguide structures. The infinite slab and circular waveguides that we know are not practical for use on a substrate because
the slab waveguide has no lateral confinement and the circular fiber is not compatible with the planar processing technology
being used to make planar structures. The rectangular waveguide is the natural structure. In this review, we have discussed
several analytical methods for analyzing the mode structure of rectangular structures, beginning with a wave analysis based
on the pioneering work of Marcatili. We study three basic techniques with examples to compare their performance levels. These
are the analytical approach developed by Marcatili, the perturbation techniques, which improve on the analytical solutions
and the effective index method with examples.
T Srinivas received the B.Sc. (Hon.) degree from Nehru Science College, Hydrabad and M.E. (Int.) and Ph.D. dgrees from the Indian Institute
of Science, Bangalore, India. He was a Postdoctoral Research Fellow at Toyohashi University of Technology, Japan from 1992
to 1996. He is currently an Associate Professor with the Department of Electrical Communication Engineering, Indian Institute
of Science. His areas of interests are optical communication networks, integrated optics, micro-opto-electrical-mechanical
systems (MOEMS) and fiberoptic sensors 相似文献
79.
设$\varphi$为群${\rm Aut}(N)$的同态,记$H_\varphi\times N$为群$N$借助于群$H$的半直积.设$G$为有限不可解群,本文证明: 若$G$中最高阶元素个数为40, 则$G$同构于下列群之一:(1)~$Z_{4\varphi}\times A_5$,\,${\rm ker}\varphi=Z_2$; (2)~$D_{8\varphi}\times A_5,\,{\rm ker}\varphi=Z_2\times Z_2$; (3)~$G/N=S_5$, $N=Z(G)=Z_2$; (4)~$G/N=S_5$, $N=Z_2\times Z_2,\,N\cap Z(G)=Z_2$. 相似文献
80.
The dynamical properties of Rydberg hydrogen atom near a metal surface are presented by using the methods of phase space analysis
and closed orbit theory. Transforming the coordinates of the Hamiltonian, we find that the phase space of the system is divided
into vibrational and rotational region. Both the Poincaré surface of section and the closed orbit theory verify the same conclusion
clearly. In this paper we choose the atomic principal quantum number asn=20. The dynamical character of the exited hydrogen atom depends sensitively on the atom-surface distanced. Whend is sufficiently large, the atom-surface potential can be expressed by the traditional van der Waals force and the system
is integrable. Whend becomes smaller, there exists a critical valued
c. Ford>d
c, the system is near-integrable and the motion is regular. While chaotic motion appears ford<d
c, and the system tends to be non-integrable. The trajectories become unstable and the electron might be captured onto the
metal surface. 相似文献