Results 241 to 250 of about 787,470 (297)
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The Journal of Chemical Physics, 1998
A rigorous definition of atomic orbitals that invokes concepts of the quantum-mechanical theory of atoms in molecules is presented. Being free of any references to nuclei-centered basis functions, this new definition is universally applicable to wave functions furnished by all types of electronic structure calculations. The atomic orbitals in molecules
Jerzy Cioslowski, Andrew Liashenko
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A rigorous definition of atomic orbitals that invokes concepts of the quantum-mechanical theory of atoms in molecules is presented. Being free of any references to nuclei-centered basis functions, this new definition is universally applicable to wave functions furnished by all types of electronic structure calculations. The atomic orbitals in molecules
Jerzy Cioslowski, Andrew Liashenko
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Atomic electronegativities in molecules
Chemical Physics Letters, 2015In this letter, we propose a straightforward evaluation of atomic electronegativities within the framework of Bader's atoms-in-molecules theory, based on the basin decomposition of the molecular electronic chemical potential derived from the Kohn-Sham equations through the non-interacting kinetic energy.
Tognetti, Vincent +2 more
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1993
We focus on the properties of a common species presented in weakly connected spatially distinct components. The classical two-phase interface serves as introduction. For the electron fluid of a system of atoms in a molecule, we introduce replica systems and then carry out a unitary transformation of the joint annihilation-creation fields to approximate
Nikos Georgopoulos, J. K. Percus
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We focus on the properties of a common species presented in weakly connected spatially distinct components. The classical two-phase interface serves as introduction. For the electron fluid of a system of atoms in a molecule, we introduce replica systems and then carry out a unitary transformation of the joint annihilation-creation fields to approximate
Nikos Georgopoulos, J. K. Percus
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Properties of atoms in molecules: Atomic polarizabilities
The Journal of Chemical Physics, 1990The theory of atoms in molecules is applied to the determination of the atomic and group contributions to the molecular polarizability in diatomic and polyatomic systems, covering a wide range of atomic interactions. The calculations are performed through the use of coupled-perturbed Hartree–Fock theory.
Keith E. Laidig, Richard F. W. Bader
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On 'collective excitations' in atoms and molecules
Journal of Physics B: Atomic and Molecular Physics, 1976An analysis of 'collective excitations' in the wavefunction picture and conditions for their occurrence are presented.
Νικολαΐδης, Κλεάνθης A. +2 more
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Journal of Molecular Structure: THEOCHEM, 1988
Abstract The role of models in quantum chemistry is discussed and their gnoseological role is stressed. The simple independent atom (IAM) and modified atom (MAM) models are described. Their applications in rationalizing molecular structure and some molecular properties are considered.
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Abstract The role of models in quantum chemistry is discussed and their gnoseological role is stressed. The simple independent atom (IAM) and modified atom (MAM) models are described. Their applications in rationalizing molecular structure and some molecular properties are considered.
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Superradiance in atoms and molecules
Contemporary Physics, 1981Abstract This article reviews the present status of superradiance in atoms and molecules. The introductory section describes the important physical properties of superradiant emission, and presents the important experimental features. A simple theoretical formulation, based on the coupled Maxwell-Schrodinger equations, is described.
J. C. Macgillivray, M. S. Feld
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1990
Abstract The molecular structure hypothesis - that a molecule is a collection of atoms linked by a network of bonds - was forged in the crucible of nineteenth-century experimental chemistry and has continued to serve as the principal means of ordering and classifying the observations of chemistry.
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Abstract The molecular structure hypothesis - that a molecule is a collection of atoms linked by a network of bonds - was forged in the crucible of nineteenth-century experimental chemistry and has continued to serve as the principal means of ordering and classifying the observations of chemistry.
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Orbitals in atoms and molecules
Journal of Inorganic and Nuclear Chemistry, 1963Orbitals in Atoms and Molecules By Chr. Klixbull Jorgensen. Pp. v + 162. (London: Academic Press, Inc. (London), Ltd.; New York: Academic Press, Inc., 1962.) 35s.
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Electron correlation in atoms and molecules
Physica, 1962Using a modified Rayleigh-Schrodinger perturbation scheme, it is shown that the first order correction to the Hartree-Fock function due to electron correlation effects may be written as Σi>j A(χijφ1...φi−1φi+1...φj−1φj+1...φN−φ1...φN), where the φ's are the Hartree-Fock SCF orbitals, A is the antisymmetrization operator, χij is an antisymmetrized ...
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