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Alojzy Gołębiewski 《Molecular physics》2013,111(6):1529-1542
A formula for the change of energy is derived, valid for any infinitesimal change of the hamiltonian and the wave function in CI, SCF and MC SCF theories. A general form of MC Hartree-Fock equations is derived in a somewhat new form. A closed MC theory is defined and a condition of self-consistency is derived for this theory. The role of deorthogonalization of spin orbitals is discussed. The Hellmann-Feynman theorem and the generalized Brillouin theorem are rederived in a unique and simple way. It is shown that in the case of the closed MC SCF theory the Brillouin theorem derived by Levy and Berthier can be strengthened. Formulae for generalized forces are derived, valid for closed-shell, openshell and multiconfigurational SCF theories also far from the Hartree-Fock limit. 相似文献
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Mei-Shan ZHAO 《理论物理通讯》1996,25(1):1-6
The quantum mechanical transition state reaction rates for both microcanonical and macrocanonical expressions are derived from a recently developed classical reaction rate theory. The newly derived quantum transition-state-like rates are good for both unimolecular reaction and bimolecular reaction depending on the choices of the transition state dividing surfaces. In a special choice of the transition dividing surface for bimolecular reaction, the macrocanonic rate derived in this paper is reduced to the flux-flux autocorrelation formalism derived from quantum bimolecular reactive scattering by Miller and to those obtained by Yamamo to using Ku to linear response an alysis. 相似文献
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椭圆平顶高斯光束的聚焦特性 总被引:4,自引:4,他引:0
利用级数分解法把椭圆平顶高斯光束(EFGB)分解成多个椭圆厄密-高斯模的叠加形式,利用椭圆厄密-高斯模的传输公式导出了EFGB通过非轴对称光学系统的传输公式,该公式和直接用矢量积分得出的结果是等效的.利用导出的公式,我们计算分析了EFGB通过轴对称透镜和非轴对称透镜的聚焦特性.结果表明,EFGB聚焦后,近场光强分布变化很快,特别是焦点前后,光强分布会快速旋转.另外,EFGB的聚焦特性与阶次有关. 相似文献
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《Physics letters. A》2006,355(2):156-161
The fractional Fourier transform (FRT) for a hollow Gaussian beam (HGB) is investigated. Based on the definition of FRT in the cylindrical coordinate system, analytical formulae are derived for the FRT for a HGB. By using the derived formulae, the properties of a HGB in the FRT plane are illustrated numerically. The derived formulae provide a convenient way for analyzing and calculating the FRT of a HGB. 相似文献
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Jun-Chen Su 《The European Physical Journal C - Particles and Fields》2006,47(3):757-783
A rigorous three-dimensional relativistic equation for quark–antiquark bound states at finite temperature is derived from
the thermal QCD generating functional which is formulated in the coherent-state representation. The generating functional
is derived newly and given a correct path-integral expression. The perturbative expansion of the generating functional is
specifically given by means of the stationary-phase method. Especially, the interaction kernel in the three-dimensional equation
is derived by virtue of the equations of motion satisfied by some quark–antiquark Green functions and given a closed form
which is expressed in terms of only a few types of Green functions. This kernel is very suitable to use for exploring the
deconfinement of quarks. To demonstrate the applicability of the equation derived, the one-gluon exchange kernel is derived
and described in detail.
PACS 05.30.-d, 67.40.Db, 11.15.-q, 12.38.-t, 11.10.St. 相似文献
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Vertically aligned one-dimensional ZnO nanowire arrays have been synthesized by a hydrothermal method on sol–gel derived ZnO films. Sol–gel derived ZnO films and corresponding ZnO nanowire arrays have been characterized by X-ray diffraction and field-emission scanning electron microscopy. The effect of sol–gel derived ZnO film surface on the morphology of ZnO nanowire arrays has been investigated. The authors suggest from our investigation that sol–gel derived ZnO films affect the growth of one-dimensional ZnO nanostructures. Not only crystalline ZnO films but also amorphous ones can act as a scaffold for ZnO nucleus. Tilted ZnO micro-rods are grown on ZnO gel films, whereas vertically aligned ZnO nanowire arrays are grown on nanometer-sized ZnO grains. The average diameter of ZnO nanowire arrays are correlated strongly with the grain size of sol–gel derived ZnO films. 相似文献
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Robert L. Bish 《哲学杂志》2013,93(25):3343-3357
An analytical solution is derived for the problem of shearing of a thin disc of incompressible rigid, plastic strain-hardening material. The solution is obtained by a methodology introduced by the author in previous publications, relying fundamentally on continuity of the rotation-rate vector field. A variational theorem is derived which shows that the velocity vector field is unique if the boundary values are properly prescribed. The derived solution is compared to experiments, with which it shows good agreement. 相似文献
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Spectrometer functions and peak heights have been derived analytically for a 127° capacitor on the basis of the corresponding second-order trajectory equations. The expressions derived are discussed under the various conditions appropriate to the use of the capacitor as a monochromator or as an analyser. A figure of merit is introduced, and optimisation of the geometrical parameters according to this criterion is carried out. The maximum angular acceptance of a capacitor is discussed, and the spurious-background problem is reconsidered. Finally, a space-charge model is derived which describes the main experimental observations for the first time. The calculus derived in this paper and exemplified for a 127° capacitor can be applied equally to other geometries if the corresponding trajectory equations are known. 相似文献
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《Physics letters. [Part B]》1987,194(4):530-534
A generalized Langevin equation for fermion field is first derived within the framework of the stochastic quantization. Based on it, the chiral anomaly is derived directly from the stationary property of the pseudoscalar density. This approach is convenient to observe the quantum origin of anomalies. The conservation law of the vector current is also derived in a similar way. 相似文献
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A decentered flattened Gaussian beam (DEFGB), is defined by a tensor method. The propagation formula for a DEFGB passing through an axially nonsymmetrical paraxial optical system is derived through vector integration. The derived formula can be reduced to the formula for a generalized decentered elliptical flattened Gaussian beam under certain condition. As an example application of the derived formula, the propagation characteristics of a DEFGB in free space are calculated and discussed. As another example we have studied the properties of superposition with radial array consisted by DEFGB. 相似文献
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Electronic polarizabilities of ions in II–VI crystals recently derived by Jain et al. are criticised. It has been demonstrated that the polarizabilities derived by Boswarva in alkaline earth chalcogenides on the basis of the additivity rule using crystal refraction data are consistent with those derived in the present paper employing a theoretical model originally developed by Ruffa. 相似文献
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Fractional Fourier transform for partially coherent beam in spatial-frequency domain 总被引:1,自引:0,他引:1
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By using Fourier transform and the tensor analysis method, the fractional Fourier transform (FRT) in the spatial-frequency domain for partially coherent beams is derived. Based on the FRT in the spatial-frequency domain, an analytical transform formula is derived for a partially coherent twisted anisotropic Gaussian-Schell model (GSM) beam passing through the FRT system. The connections between the FRT formula and the generalized diffraction integral formulae for partially coherent beams through an aligned optical system and a misaligned optical system in the spatial-frequency domain are discussed, separately. By using the derived formula, the intensity distribution of partially coherent twisted anisotropic GSM beams in the FRT plane are studied in detail. The formula derived provide a convenient tool for analysing and calculating the FRTs of the partially coherent beams in spatial-frequency domain. 相似文献
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A closed system of surface elasticity equations was derived in terms of surface quantities defined as integrals of respective excess bulk quantities normal to the interface. The equations were consistently linearized for the case of small strains. It is shown that these equations are more general than the Shuttleworth equations. Equations of this type were also derived for the particular case of an interface formed by a thin layer with constant properties. The derived equations were used to consider bending of a plate under pressure applied to both sides. 相似文献
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Some notes on analytical derived loudspeaker arrays with uniform radiation characteristics are presented. The array coefficients are derived via analytical means and compared with so-called maximal flat sequences known from telecommunications and information theory. It appears that the newly derived array, i.e., the quadratic phase array, has a higher efficiency than the Bessel array and a flatter response than the Barker array. The method discussed admits generalization to the design of arrays with desired nonuniform radiating characteristics. 相似文献
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Derived Brackets 总被引:3,自引:1,他引:2
Yvette Kosmann-Schwarzbach 《Letters in Mathematical Physics》2004,69(1-3):61-87
We survey the many instances of derived bracket construction in differential geometry, Lie algebroid and Courant algebroid theories, and their properties. We recall and compare the constructions of Buttin and of Vinogradov, and we prove that the Vinogradov bracket is the skew-symmetrization of a derived bracket. Odd (resp., even) Poisson brackets on supermanifolds are derived brackets of canonical even (resp., odd) Poisson brackets on their cotangent bundle (resp., parity-reversed cotangent bundle). Lie algebras have analogous properties, and the theory of Lie algebroids unifies the results valid for manifolds on the one hand, and for Lie algebras on the other. We outline the role of derived brackets in the theory of Poisson structures with background'. 相似文献
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Chongwei Zheng 《Optics Communications》2006,259(2):445-448
The fractional Fourier transform (FRT) is applied to off-axis elliptical Gaussian beam (EGB). An analytical formula is derived for the FRT of off-axis EGB in terms of the tensor method. The corresponding tensor ABCD law for performing the FRT of off-axis EGB is also obtained. By using the derived formulae, numerical examples are given. The derived formulae provide a convenient way for analyzing and calculating the FRT of off-axis EGB. 相似文献
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With a new projective equation, a series of solutions of the (2-J-1)-dimensional dispersive long-water wave system (LWW) is derived. Based on the derived solitary wave solution, we obtain some special fractal localized structures and chaotic patterns. 相似文献