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991.
M R M Witwit 《Pramana》1994,42(4):333-340
The Schrödinger equation with the potentialV(r)=D[exp(?2β(r?r e))?2exp(?β(r?r e))] is treated in the framework of the hypervirial-renormalization parameter scheme. The energy eigenvalues of various eigenstates for different molecules are calculated. 相似文献
992.
Ping Lin. 《Mathematics of Computation》2003,72(242):657-675
In many applications materials are modeled by a large number of particles (or atoms) where any one of particles interacts with all others. Near or nearest neighbor interaction is expected to be a good simplification of the full interaction in the engineering community. In this paper we shall analyze the approximate error between the solution of the simplified problem and that of the full-interaction problem so as to answer the question mathematically for a one-dimensional model. A few numerical methods have been designed in the engineering literature for the simplified model. Recently much attention has been paid to a finite-element-like quasicontinuum (QC) method which utilizes a mixed atomistic/continuum approximation model. No numerical analysis has been done yet. In the paper we shall estimate the error of the QC method for this one-dimensional model. Possible ill-posedness of the method and its modification are discussed as well.
993.
Niranjan Das 《Pramana》2004,62(1):135-142
In the present paper, a study of the deep-sea water wave caused by an oscillatory wind stress due to the atmospheric depression,
resulting in spiral cyclonic wind pressure on the surface of the sea is made. It has been observed that the motion of the
water wave in the case of wind stress exhibits a greater elevation on the sea surface asg the acceleration due to gravity decreases and maintains the oscillatory nature with the increase of time. For the case of
spiral cyclonic motion for which the sea surface experiences the elliptical pressure on the surface, the motion diminishes
asg diminishes and oscillates with the variation of time. The motion also diminishes asymptotically as the radius vector of the
elliptical pressure approaches unity. 相似文献
994.
995.
声子之间相互作用对磁场中表面极化子的诱生势的影响 总被引:6,自引:3,他引:3
研究极性晶体中电子与表面光学(SO)声子和体纵光学(BO)声子耦合弱的表面磁极化子的性质,采用线性组合算符和微扰法导出了极性晶体中表面磁极化子的有效哈密顿量。讨论了反冲效应中不同波矢声子之间相互作用对表面磁极化子诱生势的影响。 相似文献
996.
997.
A suitable temperature dependence is introduced into the force parameters of the Lennard-Jones potential by taking the free-energy
average of the Rowlinson potential. The resulting temperature-dependent parameters are used to calculate the effective potential,
which is plotted for water vapour at a few different temperatures. The temperature-dependence of the second virial coefficient
is shown for the cases of temperature-independent and temperature-dependent parameters of which the latter agrees very well
with experimental results. 相似文献
998.
Two methods for symmetrizing Markov processes are discussed. Letu
a(x, y) be the potential density of a Lévy process on a compact Abelian groupG. A general condition is given that guarantees thatv(x, y)=ua(x, y)+ua(y, x) is the potential density of a symmetric Lévy process onG. The second method arises by considering the linear space of one-potentialsU
1
f, withf inL
2, endowed with the inner product (U
1
f,U
1
g)=fU
1
g+gU
1
f. If the semigroup ofX(t) is normal, then the completionH of this space is the Dirichlet space of a symmetric processY(t). A set that is semipolar forX(t) is polar forY(t). 相似文献
999.
本文给出了气垫船在静水中航行时稳态船波势问题的边界元数值分析方法,根据本文的数值计算方法,可以得到气垫船行时所兴起的波浪形状以及气垫附近流场情况,由此可计算气垫所受到的兴波阻力,本文的方法适用于任意已知气压分布情况。 相似文献
1000.
The Gordon-Kim method of calculating the interatomic potentials is modified with corrections to the exchange and dispersion
interactions, and the interionic potentials in alkali-halide crystals are calculated from Roothaan-Hartree-Fock ionic wavefunctions.
The lattice constants, cohesive energies and elastic constants of NaCl, NaF, NaBr, KCl, KF, KBr, RbCl, RbF and RbBr crystals
are evaluated using the calculated interionic potentials. The agreement of the results with the experimental data is good. 相似文献