TY - CONF TI - Theoretical Description of the Electronic Structure and Spectra of Localized Sites in Large Systems AU - Whitten, J.L. T2 - American Chemical Society Meeting C2 - 1978/// CY - Indianapolis, IN DA - 1978/// PY - 1978/5// ER - TY - JOUR TI - A theoretical study of the reaction of methane with methyl radical using several different ab initio and semiempirical methods AU - Rayez-Meaume, M. T. AU - Dannenberg, J. J. AU - Whitten, J. L. T2 - Journal of the American Chemical Society AB - ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTA theoretical study of the reaction of methane with methyl radical using several different ab initio and semiempirical methodsM. T. Rayez-Meaume, J. J. Dannenberg, and J. L. WhittenCite this: J. Am. Chem. Soc. 1978, 100, 3, 747–749Publication Date (Print):February 1, 1978Publication History Published online1 May 2002Published inissue 1 February 1978https://doi.org/10.1021/ja00471a014RIGHTS & PERMISSIONSArticle Views115Altmetric-Citations26LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (384 KB) Get e-Alerts Get e-Alerts DA - 1978/2// PY - 1978/2// DO - 10.1021/ja00471a014 VL - 100 IS - 3 SP - 747-749 J2 - J. Am. Chem. Soc. LA - en OP - SN - 0002-7863 1520-5126 UR - http://dx.doi.org/10.1021/ja00471a014 DB - Crossref ER - TY - JOUR TI - Electron density and density matrix approximations using potential energy error bounds AU - Pakkanen, Tapani A. AU - Whitten, J. L. T2 - The Journal of Chemical Physics AB - The possibility of simplifying expansions of the total electron density, ρ (1), and the first order density matrix, γ (1,1′), derived from a given total wavefunction is considered based on the minimization of positive definite error bound integrals, ε=〈ρ (1)−ρ′ (1) ‖ν12‖ρ (2)−ρ′ (2) 〉 and εγ=〈γ (1,2)−γ′ (1,2) ‖ν12‖γ (1,2) −γ′ (1,2) 〉. Expansions, ρ′ and γ′, are in terms of a subset of the full basis and are designed for iterative use in energy variational calculations. In all of a variety of cases investigated, simple one-center expansions are found to be very accurate for the ρ expansion which determines the total coulombic energy of the system. However, correspondingly simple, one-center γ (1,2), expansions produce significant errors in the exchange, self-energy when the electron distribution is highly delocalized requiring that important two-center distributions be included for accurate calculations. Applications to localized electron distributions and to problems in which a lower level of accuracy is acceptable are discussed. DA - 1978/9// PY - 1978/9// DO - 10.1063/1.436819 VL - 69 IS - 5 SP - 2168-2174 J2 - The Journal of Chemical Physics LA - en OP - SN - 0021-9606 1089-7690 UR - http://dx.doi.org/10.1063/1.436819 DB - Crossref ER - TY - JOUR TI - Interaction between matrix isolated nickel difluoride and carbon monoxide. An ab initio molecular orbital study AU - Besnainou, S. AU - Whitten, J. L. T2 - Journal of the American Chemical Society AB - ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInteraction between matrix isolated nickel difluoride and carbon monoxide. An ab initio molecular orbital studyS. Besnainou and J. L. WhittenCite this: J. Am. Chem. Soc. 1978, 100, 12, 3692–3698Publication Date (Print):June 1, 1978Publication History Published online1 May 2002Published inissue 1 June 1978https://doi.org/10.1021/ja00480a006Request reuse permissions Article Views66Altmetric-Citations7LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (2 MB) Get e-Alertsclose Get e-Alerts DA - 1978/6// PY - 1978/6// DO - 10.1021/ja00480a006 VL - 100 IS - 12 SP - 3692-3698 J2 - J. Am. Chem. Soc. LA - en OP - SN - 0002-7863 1520-5126 UR - http://dx.doi.org/10.1021/ja00480a006 DB - Crossref ER - TY - JOUR TI - Multiphoton ionization spectroscopy: A theoretical analysis of the NO spectrum AU - Cremaschi, P. AU - Johnson, P. M. AU - Whitten, J. L. T2 - The Journal of Chemical Physics AB - The multiphoton ionization spectrum of the NO molecule is described theoretically by calculations of absorption and ionization cross-sections. Both perturbation theoretic (short-time) and rate equation (long-time) descriptions of the stepwise excitation and ionization process are considered. Under the present experimental conditions the two approaches are shown to give qualitatively similar results. Two cases of four-photon absorption are treated: in the first, called a 2+2 process, resonance occurs on absorption of the second photon; and in the second, 3+1 process, resonance occurs at the third photon level. For the wavelength range considered, there is one state, the A 2Σ+, in the former category and six possible choices for the latter. The 2+2 process is shown to have the higher intensity. For most of the resonant states, relative calculated ionization cross sections are in accord with experiment. DA - 1978/11/15/ PY - 1978/11/15/ DO - 10.1063/1.436445 VL - 69 IS - 10 SP - 4341-4348 J2 - The Journal of Chemical Physics LA - en OP - SN - 0021-9606 1089-7690 UR - http://dx.doi.org/10.1063/1.436445 DB - Crossref ER -