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High Temperature Elastic Diffuse Neutron Scattering Study of the Defect Structure in TiN0.82

  • Thierry Priem
  • Brigitte Beuneu
  • Charles de Novion

Abstract

Titanium mononitride TiNx has the f.c.c. rocksalt crystal structure, with nitrogen vacancies accommodating the non-stoichiometry for 0.50 < x < 1.00 (Ref. 1) For 0.5 < x < 0.6, a quadratic Ti2N superstructure, where the nitrogen vacancies are long-range ordered, of space group I41/amd and characterized by (1 1/2 0) type superlattice reflections, occurs below 800 °C. 2 For larger nitrogen concentrations (0.6 < x < 0.9), diffuse streaks were observed on electron diffraction patterns, and qualitatively interpreted in terms of short-range ordering (SRO) of nitrogen vacancies.3 However, recent X-ray diffuse scattering measurements on the isomorphous compound NbC0.72 showed that this diffuse intensity is dominated by static displacements of the metal atoms.4 Therefore, because of their larger scattering amplitudes by light atoms, neutrons should be preferred to study the ordering contribution to the diffuse scattering. This is the object of the present paper. Preliminary results on a sample cooled at room temperature have been published recently.5

Keywords

Pair Potential Diffuse Intensity Diffuse Scattering Nitrogen Vacancy Transition Metal Carbide 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • Thierry Priem
    • 1
  • Brigitte Beuneu
    • 1
  • Charles de Novion
    • 1
  1. 1.CEA/IRDI/DMECN/DTech, Laboratoire des Solides IrradiésEcole PolytechniquePalaiseau CédexFrance

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