Calculated ionization potentials of the linear alkanes

Brailsford, David F.; Ford, Brian

doi:10.1080/00268977000100691

Cited by 37 publications

(12 citation statements)

References 7 publications

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“…A typical computational paper from that group at about that time is the one by David Brailsford and Brian Ford on the ionization potentials of the linear alkanes. 45 The paper is interesting not only for its content, but also for the future careers of the authors. David Brailsford went on to be professor and head of the department of Computer Science at Nottingham, and Brian Ford became director of the Numerical Algorithms Group (NAG), a group that made such enormous contributions to software developments in the 1970s and 1980s and indeed, still do make.…”

Section: Emerging From the 1960smentioning

confidence: 99%

The Development of Computational Chemistry in the United Kingdom

Smith

Sutcliffe

1996

Reviews in Computational Chemistry

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Section: Emerging From the 1960smentioning

confidence: 99%

The Development of Computational Chemistry in the United Kingdom

Smith

Sutcliffe

1996

Reviews in Computational Chemistry

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“…Notwithstanding this handicap the numerical values derived for a limited set of matrix elements by Brailsford & Ford [9] and by Murrell & Schmidt [lo] are in rather good agreement with each other and they have been used with success for the interpretation of the photoelectron spectra of other hydrocarbons [ 141.…”

Section: Discussionmentioning

confidence: 94%

“…of ethane, met with difficulties [8-101 it became now possible to use this detailed information for a recalibration of the LCBO-model. In this connection the work of Brailsford & Ford [9], and that of Murrell & Schmidt [lo] should be mentioned. In both cases the number of different types of equivalent interaction elements Hxy,x,y, (e.g.…”

Section: Discussionmentioning

confidence: 98%

“…the mean self-energies A= -15.8 eV and mean vicinal cross-terms B = -2.2 eV defined in (8) should be compared to those derived by Brailsford & Ford [9] and by Murrell & Schmidt [ 101 who calibrated their equivalent orbital model using only the C2,-band of propane, n-butane, n-pentane and n-hexane, or of methane, ethane, propane, iso-butane and neo-pentane respectively. …”

Section: ) If Two Localized Equivalent Orbitalsmentioning

confidence: 99%

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Application of the Equivalent Bond Orbital Model to the C_2s‐Ionization Energies of Saturated Hydrocarbons

Bieri

Dill

Heilbronner

et al. 1977

Helvetica Chimica Acta

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SummaryIt is shown that the ab znitio STO-3G treatment applied to simple saturated linear, branched and cyclic hydrocarbons, assuming standard geometries, yields orbital energies e p -3 G for their canonical orbitals yl which correlate perfectly with the observed C2, ionization energies If", if Koopmuns' approximation is accepted.Applying the Foster-Boys localization procedure to these canonical orbitals yJ leads to localized orbitals Ap and their corresponding Hartree-Fock matrix FA=(FAJ. An examination of the matrix elements F, 1,, . z.e. of the self-energies A,= F, ,~L of the localized CC-and CH-orbitals 1, and of the cross terms F,,pv (p # v) between them, leads to the conclusion that a satisfactory approximation should be obtained by setting A,=A for all p, F, ,,,= B if A,L and 2, are vicinal and neglecting all other cross terms. The resulting model is nothing but the well-known equivalent bond orbital model of Lennard-Jones & Hall, which however can now be calibrated using the known C2,-ionization energies of hydrocarbons. Due to the discrete structure and the wider range ( N 8 eV) of the Czs band systems in the photoelectron spectra of these molecules this leads to a more satisfactory parametrization than using the narrower and badly resolved Czp band system.Comparison of calculated band positions using the calibrated model with observed C2,-band ionization energies for a series of hydrocarbons reveals that the simple equivalent bond orbital model is better than one might have expected.

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“…It has proved convenient to derive the latter from simple equivalent orbital models 111, i.e. treatments which are easily parametrized [2] and thus allow the transfer of information derived from one set of spectra to those of other related systems In connection with a detailed investigation of the photoelectron spectra of oxides, in particular of benzene oxides and their valence isomers (e.g. 1 -+ 1') and of 2, Freiburg i. Br.…”

mentioning

confidence: 99%

Photoelectron Spectra of Unsaturated Oxides. I. 1,4‐Dioxin and related systems

Bloch

Brogli

Heilbronner

et al. 1978

Helvetica Chimica Acta

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SummaryThe He (Ia) photoelectron spectra of the four unsaturated oxides 3,4-dihydropyran (6), y-pyran (7), 2,3-dihydro-1,4-dioxin (9) and 1,4-dioxin (10) are reported and analysed. Band assignments are based on ab-initio calculations, using the STO-3G basis set. The proposed orbital sequences (with reference to the coordinate systems given in Table 1 ) are, for the top three orbitals: 6, n , no, nn; 7, 3bl(n), la,(n), l l a , (u); 9, 11b(n), 12a(a), l l a ( n ) ; 10, 2b3,(n), 1blg(n), 6a,(.). Finally the (almost) localized n-orbitals have been computed by the Foster-Boys localization procedure.Certainly one of the most successful techniques for assigning photoelectron spectra of organic compounds has been the empirical correlation procedure, which consists in recording the photoelectron spectra of a series of closely related compounds in which one or more structural features have been varied in a systematic fashion. The corresponding spectral changes, e.g. shifts in band positions and/or variations in the Franck-Condon contours, are then linked to the differences in structure of the individual molecules with the help of quantum-mechanical rules of thumb. It has proved convenient to derive the latter from simple equivalent orbital models 111, i.e. treatments which are easily parametrized [2] and thus allow the transfer of information derived from one set of spectra to those of other related systems In connection with a detailed investigation of the photoelectron spectra of oxides, in particular of benzene oxides and their valence isomers (e.g. 1 -+ 1') and of 2, Freiburg i. Br.

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Calculated ionization potentials of the linear alkanes

Cited by 37 publications

References 7 publications

The Development of Computational Chemistry in the United Kingdom

The Development of Computational Chemistry in the United Kingdom

Application of the Equivalent Bond Orbital Model to the C_2s‐Ionization Energies of Saturated Hydrocarbons

Photoelectron Spectra of Unsaturated Oxides. I. 1,4‐Dioxin and related systems

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Calculated ionization potentials of the linear alkanes

Cited by 37 publications

References 7 publications

The Development of Computational Chemistry in the United Kingdom

The Development of Computational Chemistry in the United Kingdom

Application of the Equivalent Bond Orbital Model to the C2s‐Ionization Energies of Saturated Hydrocarbons

Photoelectron Spectra of Unsaturated Oxides. I. 1,4‐Dioxin and related systems

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Product

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Application of the Equivalent Bond Orbital Model to the C_2s‐Ionization Energies of Saturated Hydrocarbons