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881.
Masahide Ohno 《Journal of Electron Spectroscopy and Related Phenomena》2003,130(1-3):19-24
The 4s- and 4p- XPS spectra of Xe gas, XeF2 molecule and XeF4 molecule are calculated by an ab-initio atomic many-body theory. The 4s-peak and the prominent ‘4p’-peak are predicted well by the present theory. In XeF2 and XeF4 the spectral lines observed below the 4d-double ionization threshold are the 4d−24f multiplet states strongly perturbed by the interaction with the initial 4p1/2-hole state. They are very similar to the spectral lines which emerge with an increase in atomic number (e.g. Ba). 相似文献
882.
Soliton solutions are among the more interesting solutions of the (2+1)-dimensional integrable Calogero-Degasperis-Fokas (CDF) equation. We previously derived a complete group classiffication for the CDF equation in 2+1 dimensions. Using classical Lie symmetries, we now consider traveling-wave reductions with a variable velocity depending on an arbitrary function. The corresponding solutions of the (2+1)-dimensional equation involve up to three arbitrary smooth functions. The solutions consequently exhibit a rich variety of qualitative behaviors. Choosing the arbitrary functions appropriately, we exhibit solitary waves and bound states.__________Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 144, No. 1, pp. 44–55, July, 2005. 相似文献
883.
We provide a demonstration of the integrability of a classical model of an infectious disease which neither kills nor induces autoimmunity by means of the Painlevé analysis and use the Lie theory of transformation groups to present an explicit solution. 相似文献
884.
885.
Daniel Neuenschwander 《Journal of Theoretical Probability》1992,5(1):217-222
We prove that on simply connected step 2-nilpotent Lie groupsG any limit of a commutative infinitesimals triangular system of probability measures which are either all symmetric or supported by some discrete subgroupH is infinitely divisible onG resp.H. 相似文献
886.
Consider evolution of density of a mass or a population, geographically situated in a compact region of space, assuming random creation-annihilation and migration, or dispersion of mass, so the evolution is a random measure. When the creation-annihilation and dispersion are diffusions the situation is described formally by a stochastic partial differential equation; ignoring dispersion make approximations to the initial density by atomic measures and if the corresponding discrete random measures converge “in law” to a unique random measure call it a solution. To account for dispersion Trotter's product formula is applied to semiflows corresponding to dispersion and creation-annihilation. Existence of solutions has been a conjecture for several years despite a claim in ([2], J. Multivariate Anal. 5, 1–52). We show that solutions exist and that non-deterministic solutions are “smeared” continuous-state branching diffusions. 相似文献
887.
For infinitely multiple exponentials with two alternating exponents, we construct continuations to unbounded domains, so that these continuations are the limit functions of sequences of finitely multiple exponentials. We prove that, for different exponents, such a continuation is unique in the class of continuously differentiable functions. We extend the domain of existence of infinitely multiple exponentials. For exponents with the same signs, this domain remains bounded, while for exponents with different signs, it coincides with the number axis. 相似文献
888.
Luis Rincn Rafael Almeida David García Aldea 《International journal of quantum chemistry》2005,102(4):443-453
This article studies the cooperativity present in hydrogen fluoride clusters, (FH)n, by means of a many‐body decomposition of the binding energy. With the aim of quantifying how the results depend on the calculation level, the partition was performed from dimer to hexamer at the RHF, MP2, and density functional (B3LYP) levels, and for the heptamer and octamer at the RHF and B3LYP levels, using a 6‐31++G(d, p) basis set in all cases. We obtain that, for a proper representation of the cooperative effects in hydrogen fluoride, at least the inclusion of the three‐body terms is fundamental. The contributions are found to be underestimated at the RHF level and overestimated at the B3LYP level, with respect to the MP2 results. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 相似文献
889.
After a short exposition of the theory of local and nonlocal symmetries and conservation laws for systems of PDEs, results on these and the recursion operator are listed for the system of PDEs ux=vwx, vy=uwy, uv+wxx+wyy=0. In between the methods of computation are explained. 相似文献
890.
The roles of orbital, spin and permutation symmetries in the extended Hartree-Fock (EHF) wavefunction are investigated in relation to the applications of group theory to chemical reactions. The utility of the magnetically ordered set for an extended HF calculation is pointed out. The relative stabilities among linear Hückel and Möbius three-center three-electron (3,3) systems are investigated by the generalized Hartree-Fock (GHF) and EHF methods in order to confirm the reliability of the valence-bond (VB) selection rule for free radical reactions. 相似文献