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101.
Rodrigo A. Lemos Silva Demetrio A. da Silva Filho Megan E. Moberg Ted M. Pappenfus Daron E. Janzen 《Molecules (Basel, Switzerland)》2021,26(18)
X-ray structural determinations and computational studies were used to investigate halogen interactions in two halogenated oxindoles. Comparative analyses of the interaction energy and the interaction properties were carried out for Br···Br, C-H···Br, C-H···O and N-H···O interactions. Employing Møller–Plesset second-order perturbation theory (MP2) and density functional theory (DFT), the basis set superposition error (BSSE) corrected interaction energy (Eint(BSSE)) was determined using a supramolecular approach. The Eint(BSSE) results were compared with interaction energies obtained by Quantum Theory of Atoms in Molecules (QTAIM)-based methods. Reduced Density Gradient (RDG), QTAIM and Natural bond orbital (NBO) calculations provided insight into possible pathways for the intermolecular interactions examined. Comparative analysis employing the electron density at the bond critical points (BCP) and molecular electrostatic potential (MEP) showed that the interaction energies and the relative orientations of the monomers in the dimers may in part be understood in light of charge redistribution in these two compounds. 相似文献
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We have calculated the rates for ?(1S,2S) → scalar or pseudoscalar +γ, including upsilon wavefunction effects. For a scalar we find that bound state effects reduce B(25)/B(1S) by 20–30%. For a pseudoscalar these effects enhance B(2S)/B(1S) by 5%. 相似文献
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Finite and Infinite Systems of Interacting Diffusions: Cluster Formation and Universality Properties
We study some aspects of the relationship between the long time behaviour of systems with a finite but large number of components and their idealizations with countably many components. The following class of models is considered in detail, which contains examples occuring in population growth and population genetic models. 相似文献
108.
Martha C. Mitchell Alon V. McCormick H. Ted Davis 《Zeitschrift für Physik B Condensed Matter》1995,97(2):353-360
The Tarazona model of molecular density functional theory is used to determine the adsorption isotherm and the density distribution of xenon atoms in zeolite NaA. We consider the alpha cage of NaA to be fully three-dimensional and we introduce a basis set for the density distribution to make the solution computationally tractable. The results of this density functional theory model are compared to previous results of grand canonical Monte Carlo simulations for the same system.We dedicate this paper to Professor Herbert Wagner, whose excellent contributions to density functional theory typify his valuable role in the advancement of statistical physics 相似文献
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The usual ratio of an integral formula for the likelihood ratio of a maximal invariant in a group model is shown to be correct under assumption that the denominator integral is finite almost everywhere. The limitation of this assumption is discussed, and an application to invariant suffciency is given. 相似文献