Results 251 to 260 of about 4,690,653 (292)
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Modeling the electron density kernels
Journal of Computational Chemistry, 2011AbstractExisting approximation to the softness kernel, successfully explored in earlier work, has been extended; the normal Gauss distribution function has been used instead of the Dirac delta. The softness kernel becomes continuous functions in space and may be used to calculate the linear response function of the electron density.
Pawel Szarek, Ludwik Komorowski
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Fitting spheres to electron density
Proceedings of the twenty-seventh annual symposium on Computational geometry, 2011X-ray crystallography produces molecular models (spheres for every atom of the molecule) from electron density maps (distribution of electrons over 3d space). These maps seldom have enough resolution to identify hydrogens, which are added later using simple geometric rules.
Jack Snoeyink, Vishal Verma
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Electron density to electron momentum density: The use of an energy constraint
Physical Review A, 1983A modification of the Burkhardt, K\'onya, Coulson, and March (BKCM) procedure [Phys. Rev. A 24, 2906 (1981)], enabling an estimation of electron momentum density exclusively from the knowledge of an atomic electron density, has been presented. A known value of the electronic energy has been employed as a constraint in effecting this modification ...
Shridhar R. Gadre +2 more
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Symmetry measures of the electron density
Journal of Computational Chemistry, 2010AbstractIn this communication we define electronic symmetry operation and symmetry group measures, eSOM and eSGM, respectively, develop the basic algorithms to obtain them, and give some examples of the possible applications of these new computational tools. These new symmetry measures based on the electron density have been tested in an analysis of (a)
David Casanova +2 more
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Densities, density-functionals and electron fluids
Physics Reports, 1982Abstract This review article discusses, from a unified standpoint, three current approaches in applied quantum mechanics that adopt the single-particle density as a basic variable, viz. density-functional theory (DFT), quantum fluid dynamics (QFD) and study of the properties of a system through “local” quantities in three-dimensional (3D) space ...
S.K. Ghosh, B.M. Deb
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The Journal of Chemical Physics, 1987
A new method to extract atomic electron momentum density from the corresponding electron density has been proposed. The method is based upon the nonlocal density approximation (NLDA) due to Gunnarsson, Jonson, and Lundqvist; and to Alonso and Girifalco.
Shridhar R. Gadre, Subhas J. Chakravorty
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A new method to extract atomic electron momentum density from the corresponding electron density has been proposed. The method is based upon the nonlocal density approximation (NLDA) due to Gunnarsson, Jonson, and Lundqvist; and to Alonso and Girifalco.
Shridhar R. Gadre, Subhas J. Chakravorty
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Phosphaalkenes with Inverse Electron Density
European Journal of Inorganic Chemistry, 2000This review gives an account of the syntheses, structures, and properties of phosphaalkenes (RP)-P-1=(CRR3)-R-2 with an inverse electron distribution at the P-C double bond (Pdelta-Cdelta+). The chemical reactivity of compounds of this type is novel and quite surprising compared to the chemistry of "classically polarized" phosphaalkenes (Pdelta+Cdelta-)
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The Electron Density in Intermediate Scales
Communications in Mathematical Physics, 1997The density of the ground state of large neutral atoms described by Hamiltonians with Coulomb potentials between the electrons and the static nucleus of charge \(Z\) at the origin is investigated.
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Electron Density Analysis of Hyperconjugation
ChemPhysChem, 2015AbstractHyperconjugation is analyzed through the electron density of orbitals responsible for hyperconjugative interactions, which cannot be detected by means of conventional electron‐density‐based calculations. This interaction is detected through the π electron density topology, by excluding σ electron density from the total.
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