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  • 1
    Electronic Resource
    Electronic Resource
    Density functional based studies of transition states and barriers for hydrogen exchange and abstraction reactions (1995)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 102 (1995), S. 9345-9349 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The overbinding that is inherent in existing local approximations to the density functional formalism has limited the usefulness of the local density approximation (LDA) for describing phenomena that are mediated by reaction barriers. Since the generalized gradient approximation (GGA) significantly decreases the overbinding, prospects for density functional based reaction dynamics are promising. Using both LDA and GGA functionals, we determined the transition state properties for four different reactions; H2+H→H+H2, CH4+H→CH3+H2,H+CH4→CH4 +H, and CH4+CH3 →CH3+CH4. Although we find that GGA still underestimates reaction barriers, our results show that this functional leads to significant improvements of the calculated reaction barriers and energetics. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.468801
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  • 2
    Electronic Resource
    Electronic Resource
    Bonding of Endohedral Atoms in Small Carbon Fullerenes (1994)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 98 (1994), S. 7805-7810 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j100083a010
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  • 3
    Electronic Resource
    Electronic Resource
    Localized and canonical atomic orbitals in self-interaction corrected local density functional approximation (1988)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 88 (1988), S. 1807-1817 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The self-interaction corrected (SIC) version of the local spin density (LSD) approximation has been applied to the first two rows of the periodic table with particular emphasis on local orbital choice. These are the first SIC–LSD calculations for atomic systems that account for all nonspherical corrections and are based on a rigorous variational theory. The resulting total energies and orbital energies are improved in comparison to experiment and restore a desirable trend which is found in Hartree–Fock theory. We demonstrate that with a proper treatment of the SIC–LSD off-diagonal Lagrange multipliers, the viral theorem is satisfied at self-consistency.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.454104
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  • 4
    Electronic Resource
    Electronic Resource
    A new density functional for fractionally occupied orbital systems with application to ionization and transition energies (1987)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 86 (1987), S. 258-267 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The use of fractional occupation of energy levels in the self-interaction-corrected local spin density (SIC-LSD) theory of electronic energy structure is studied with reference to calculation of ionization and excitation energies. With the original form of the SIC-LSD energy functional for fractional occupation, the one-electron eigenvalues exhibit nonlinear dependence on the occupation number. A new SIC-LSD density functional for fractional occupation based on the general behavior of the universal functional is proposed. The one-electron eigenvalues derived from this new functional vary quite linearly with the occupation number. This makes it possible to obtain ionization and excitation energies by a simple numerical integration over the occupation number. A one-point integration gives ionization energies that agree on the average with the results on taking the difference in self-consistent-field total energy between the atom and the ion to within 0.4% for the atoms He, Li, Be,...,Ar. Improvement can be made by using a three-point integration over the occupation number. This method is also applied to calculate excitation energies of selected transitions for He through Ar and the results are in good agreement with the corresponding total-energy differences.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.452616
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  • 5
    Electronic Resource
    Electronic Resource
    Density-functional theory with self-interaction correction: Application to the lithium moleculea) (1985)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 82 (1985), S. 2688-2699 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The self-interaction corrected version of the local spin density (SIC-LSD) theory for electronic structure of many-electron systems has been applied to the ground state (1Σ+g) and three excited states (3Σ+u, 3Σ+g, and 3Πu) of the lithium molecule. Calculations are performed by using both the symmetry-restricted and symmetry-unrestricted molecular orbitals. To facilitate computation with high accuracy, a special curve-fitting technique is presented. With the Kohn–Sham exchange-only functional, our results are generally in good agreement with those of multiconfiguration self-consistent-field (MCSCF) calculations for the three excited states, but our calculated dissociation energy for the ground state is much lower than the MCSCF and experimental values. Inclusion of the correlation term in the density functional is found to bring the ground-state dissociation energy very close to the experimental value but has little effect on the dissociation energy of the three excited states. Based on an analysis from the standpoint of orbital charge removal energy in a manner similar to the Koopmans theorem in Hartree–Fock theory, the canonical orbitals for SIC-LSD theory are introduced and their physical significance discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.448266
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  • 6
    Electronic Resource
    Electronic Resource
    Properties of the TDAE Molecule Within Density-Functional Theory (1999)
    Springer
    Journal of cluster science 10 (1999), S. 557-571 
    Details
    ISSN: 1572-8862
    Keywords: TDAE–C60 cluster ; density-functional theory ; magnetism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Density-functional-based methodologies have been used to calculate the geometric, electronic, and vibrational properties of the TDAE molecule. The molecule has a low first-ionization energy but, in contrast to alkali atoms, releases the electron without appreciably changing the effective molecular size. In addition to ionization energies and geometries we present the vibrational spectrum of the molecule and determine the infrared (IR) and Raman intensities as well. A discussion of some of the energetics that impact the ionicity and subsequent magnetism of TDAE–C60 is presented. Further, we identify one Raman active mode, at 1682 cm−1, which is particularly interesting since it may be used to probe the TDAE charge state experimentally.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1021961209684
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  • 7
    Electronic Resource
    Electronic Resource
    Theoretical Studies of Defects in Insulators within the Framework of the Local Density Approximation (1991)
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 37 (Jan. 1991), p. 199-210 
    Details
    ISSN: 1662-9752
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/02/05/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.37.199.pdf
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  • 8
    Electronic Resource
    Electronic Resource
    A theoretical study of rare-gas diatomic molecules with the generalized-gradient approximation to density functional theory (1998)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 69 (1998), S. 619-627 
    Details
    ISSN: 0020-7608
    Keywords: Chemistry ; Theoretical, Physical and Computational Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Three popular approximations to density functional theory are used to calculate equilibrium bond lengths, atomization energies, and vibrational frequencies of 10 rare-gas diatomic molecules. We investigated the results for the local density approximation (LDA), the Perdew-Wang 91 generalized-gradient approximation (GGA-PW91), and the Perdew-Burke-Ernzerhof generalized-gradient approximation (GGA-PBE) functionals. Calculated results are well converged with respect to basis set and numerical precision. In addition, we studied the effects due to long-range 1/r6 attractions with the London formula and density functional determined atomic polarizabilities and ionization potentials. These calculations indicate that the interaction from the overlap of atomic densities and the long-range van der Waals attraction are both important for correctly predicting the total binding energy.   © 1998 John Wiley & Sons, Inc. Int J Quant Chem 69: 619-627, 1998
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
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