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Electronic-structure of Transition-metal Tetracoordinated Complexes .1. Theoretical Abinitio and Uv-photoelectron Spectroscopy Study of Palladium(II) and Platinum(II) Square-planar Acetylacetonate Complexes
No full textHe-I and He-II excited photoelectron spectra of cyclohepttatrienetricarbonyl complexes of group via metals
No full textMicrochemical and microstructural characteristics of medieval and post-medieval ceramic glaze coatings
No full textElectronic structure of xanthine and its biological methyl derivatives by u.v. photoelectron spectroscopy
No full textA new symmetry criterion based on the distance function and applications to PDE's
No full textWe prove that, if Omega subset of R-n is an open bounded starshaped domain of class C-2, the constancy over partial derivative Omega of the function phi(y) = integral(lambda(y))(0) Pi(n-1)(j=1) [1 - t kappa(j)(y)]dt implies that Omega is a ball. Here kappa(j)(y) and lambda(y) denote respectively the principal curvatures and the cut value of a boundary point y is an element of partial derivative Omega. We apply this geometric result to different symmetry questions for PDE's: an overdetermined system of Monge-Kantorovich type equations (which can be viewed as the limit as p -> +infinity of Serrin's symmetry problem for the p-Laplacian), and equations in divergence form whose solutions depend only on the distance from the boundary in some subset of their domain. (c) 2013 Elsevier Inc. All rights reserved
An Accurate Dv X-alpha Investigation of the Electronic-structure of Bis(2,4-pentanedionato)palladium(ii)
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Photoelectron spectroscopy of f-element organometallic complexes. 9. A comparative fully relativistic/nonrelativistic first-principles X.alpha.-DVM and photoelectron spectroscopic investigation of electronic structure in homologous 4f and 5f tris(.eta.5-cyclopentadienyl)metal(IV) alkoxide complexes
No full textThe electronic structure of (eta5-C5H5)3MOR (M = Ce, Th, U) complexes has been investigated by He I and He II UV photoelectron spectroscopy combined with SCF Xalpha-DVM calculations. Fully relativistic Dirac-Slater calculations were also carried out for the M = Th complex. The nonrelativistic calculations indicate that metal-ligand interactions involving the highest energy ligand orbitals involve primarily metal 5f orbitals while 6d admixtures are found for lower energy orbitals. The M-O bonding is both sigma and pi in nature and involves primarily metal 6d atomic orbitals. Evidence of a charge redistribution mechanism along the CH3 --> O --> M --> Cp3 direction provides a satisfactory explanation for the shortened M-O distances and strong propensity for nearly linear M-O-CH3 linkages observed in diffraction studies. The fully relativistic calculations show that metal d contributions are slightly underestimated at the nonrelativistic level. Such deviations do not, however, alter the overall description of the metal-ligand bonding. The nonrelativistic configuration of the metal center compares well with the relativistic data. Gas-phase ionization energies can be accurately and comparably evaluated at the computationally more efficient nonrelativistic level if optimized basis sets and potential representations are used
Electronic structure of tetracoordinate transition-metal complexes. 5. Comparative theoretical ab initio/Hartree-Fock-Slater and ultraviolet-photoelectron spectroscopic studies of building blocks for low-dimensional conductors. Dibenzo[b,i][1,4,8,11]tetraazacyclotetradecine complexes of nickel(II) and palladium(II)
No full textThe electronic structure of the Ni and Pd complexes of the title ligand have been studied by an integrated experimental He I/He II photoelectron spectroscopic as well as theoretical ab initio pseudopotential and first-principles local exchange DV-Xa approach. Theoretical calculations have provided a complete assignment of photoelectron spectra as well as useful information on the peculiarities of the valence electronic system that, in turn, is of relevance in understanding the properties of low-dimensional, partially
oxidized, [M(TAA)e], systems. Furthermore, similarities and differences between the present complexes and partially oxidized metallophthalocyanines are discussed in terms of the nature of the HOMO and of twisting motion effects upon the valence bandwidths. The present results argue that the charge transport in tetraazaannulene molecular conductors occurs via bands that are predominantly ligand pi-electron in character, and that twisting motions (librations) scarcely affect the resistivity
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