Articles
  • Charge distribution analysis of ceramic materials
  • Massimo Nespolo*, Giovanni Ferrarisa and Rudolf Hoppeb
  • Japan Science and Technology Corporation, National Institute for Materials Science, Advanced Materials Laboratory. 1-1 Namiki, Tsukuba-shi, Ibaraki 305-0044, Japan a University of Torino, Department of Mineralogical and Petrologic Sciences. Via Valperga Caluso 35, 10125 Torino, Italy b Justus-Liebig Universität, Institut für Anorganische und Analitische Chemie. Heinrich-Buff-Ring 58, D-35392 Gießen, Germany
Abstract
The Charge Distribution method is the latest development of the Pauling's idea of bond strength and is based on a geometrical analysis of the coordination polyhedra. Differently from other methods extending Pauling's approach, it uses only one empirical parameter independent from the experimental conditions, and can thus be applied equally well to structures at ambient and at extreme conditions. The kernel of the method consist in the calculation of the Effective Coordination Number (ECoN), a non-integer number that gives the weighted number of anions coordinating each cation, and the distribution of the formal oxidation numbers among all chemical bonds through the corresponding fractions of ECoN. The applications include: 1) structure validation; 2) analysis of the ordering pattern of elements substituting isomorphously; 3) analysis of the correlation between properties and structure, through the so-called Over-Under-Bonding effects. Examples are discussed in details.

Keywords: Charge Distribution, ECoN, Structure validation

This Article

  • 2001; 2(1): 38-44

    Published on Mar 31, 2001