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John A. McGinnety

Bio: John A. McGinnety is an academic researcher from Yale University. The author has contributed to research in topics: Platinum & Triphenylphosphine. The author has an hindex of 8, co-authored 16 publications receiving 224 citations.

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Journal ArticleDOI
TL;DR: The crystal and molecular structure of a disubstituted acetylene complex of palladium, [Pd{C2(CO2Me)2}(PPh3)2], has been determined from three-dimensional X-ray diffraction data as discussed by the authors.
Abstract: The crystal and molecular structure of a disubstituted acetylene complex of palladium, [Pd{C2(CO2Me)2}(PPh3)2], has been determined from three-dimensional X-ray diffraction data. The complex crystallises in space group P21/c,C2h5, of the monoclinic system, with four molecules in a unit cell of dimensions a= 11·816(3), b= 15·331(4), c= 21·891(6)A, β= 113·22(1)°. No crystallographic symmetry is imposed upon the molecules and there is one molecule in the asymmetric unit. The structural parameters were refined by least squares techniques, the R-factor on F converging to 5·2% for the 3365 reflections, collected using a four-circle diffractometer, for which F > 0. Co-ordination around palladium is approximately planar: the dihedral angle between the plane defined by the palladium and two phosphorus atoms and that defined by the palladium and the two acetylenic carbon atoms is 9·7(4)°. The acetylenic carbon–carbon separation in the complex is 1·28(1)A, longer than expected for the free acetylene. Each substituent upon acetylene is planar to a reasonable approximation and is bent away from the metal by about 35° from the CC bond axis. The acetylenic carbon atoms are separated from the metal by 2·074(6) and 2·051(6)A and the metal–phosphorus bond lengths are 2·321(2) and 2·330(2)A. This slight asymmetry in the bond lengths to palladium is tentatively ascribed to the electronic effects of the differing orientations of the substituents upon acetylene.

22 citations


Cited by
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Journal ArticleDOI
TL;DR: A complete Intermediate Neglect of Differential Overlap model suitable for the examination of transition metal complexes is described in this paper, which is characterized by the inclusion of all the one-center exchange terms necessary for rotational invariance and accurate spectroscopic predictions, as well as an accurate description of integrals involving 3D atomic orbitals.
Abstract: A complete Intermediate Neglect of Differential Overlap model suitable for the examination of transition metal complexes is described. The model is characterized by the inclusion of all the one-center exchange terms necessary for rotational invariance and accurate spectroscopic predictions, as well as an accurate description of integrals involving 3d atomic orbitals. The model is within the unrestricted Hartree-Fock formalism, and a method for spin purification is described. Problems with convergence of the self-consistent field are discussed, and a method that has been found successful in aiding the convergence is outlined. The model has been applied to many transition metal systems. In this article the results of calculations on the chlorides of Fe, Co and Cu are described. The results of these calculations are compared with experiment, and with the results of calculations by other methods.

681 citations

Book ChapterDOI
01 Jan 1984
TL;DR: As a consequence of the non-spherical symmetry of the copper(II) ion, d9 configuration, and of the influence of the Jahn-Teller, and pseudo Jahn Teller effect on six-coordinate geometries, the stereochemistries of copper( II) ion are characterized by non-rigid geometry (fluxional behaviour), and ranges of distorted geometry (Plasticity Effect) The latter may be connected by a series of Structural Pathways, which may be characterised by an "Electronic Criterion of Stereochemistry
Abstract: As a consequence of the non-spherical symmetry of the copper(II) ion, d9 configuration, and of the influence of the Jahn-Teller, and pseudo Jahn-Teller effect on six-coordinate geometries, the stereochemistries of the copper(II) ion are characterized by non-rigid geometries (fluxional behaviour), and ranges of distorted geometries (Plasticity Effect) The latter may be connected by a series of Structural Pathways, which may be characterised by an ‘Electronic Criterion of Stereochemistry’ for a related series of complexes, eg the [Cu(bipy)2X] [Y] complexes

441 citations

Journal ArticleDOI
TL;DR: In this article, a TD-DFT-based protocol was used to simulate the Cl K-edge spectra of a series of metal tetrachloride complexes and the influence of the chosen density functional, relativistics, basis set, and solvation has been systematically investigated, showing that good agreement between the calculated spectra and the relative experimental energies and intensities can be achieved by using the BP86 functional with standard polarized triple-ζ basis sets (such as the TZVP basis of Ahlrichs and co-workers).

208 citations

Journal ArticleDOI
TL;DR: A review of copper(II) stereochemistry involving structural pathways is presented in this paper in an attempt to describe and rationalise these variable stereochemistries, and new interpretations linking the Jahn-Teller effect (JTE), vibronic coupling, structure correlation analysis, structural pathways and comparative X-ray crystallography are reported.

168 citations

Book ChapterDOI
TL;DR: In this article, the relativities of coordinated acetylene in terms of a qualitative molecular orbital picture have been analyzed and the role played by auxiliary ligands of transition metals in determining the paths of catalytic oligomerization has been discussed.
Abstract: Publisher Summary The chapter discusses facets associated with the nature of the interactions between acetylenes and transition metals and to the insertion reactions of complexes closely related to catalysis. Although only scattered data are available, attempts were made to give a consistent interpretation of the relativities of coordinated acetylene in terms of a qualitative molecular orbital picture. Studies on elementary reactions of acetylenes with metal complexes are now beginning to shed some light on the nature of activation caused by complication. This activation is not a simple process. Many low-valent d 8 -d 10 metal complexes and also some early transition metal compounds with higher oxidation state are capable of activating acetylenes. In the former complexes, interaction would lead to activation of an n 2- acctylcne ligand to an η-acetylene having some radical as well as some anionic character. The chapter also focuses on the complex chemistry and catalytic oligomerizations of allene. It also describes the importance of the role played by auxiliary ligands of transition metals in determining the paths of catalytic oligomerizations. In general the thermal reaction of allene gives a complex mixture of dimers, trimers, and higher oligomers including small amounts of spiro compounds.

150 citations