Effect of 4d Transition Metal Atom Rh Doping on Thermoelectric Power, Magnetic Susceptibility, Thermal Expansion and X-Ray Photoemission Spectra in the Charge-Transfer Type Nonmetallic State of NiS

Hideya Ikoma, Masanori Matoba, Mitsuo Mikami, Shuichiro Anzai

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We report the following two remarks of the Rh impurity effect on the charge-transfer (CT) type nonmetallic state (below the nonmetal-metal transition temperature: Tt) of 3d transition metai compound NiS. (1) Although the nearest neighbourmg M-M (Ni or Rh) and S-S distances increase with increasing x, dTt/dx<0. The Rh substitution gives a broad peak with the Fermi edge. A positive sign of T-linear contribution of the thermoelectric power turns to negative one at the critical concentration (xc) in Ni1−xRhxS. Below Tt, a Curie constant is observed and increases with increasing x. It is suggested that an impurity band introduced by the Rh atoms leads a change of the electronic state of Ni atoms and the suppression of the CT gap. (2) An empirical relation (dTt/d | CN| >0) is found on Ni1−xRhxS, Ni1−dS and NiS1−ySey, where CN is the phonon-drag coefficient. The slope dTt/d | CN| becomes smaller in Ni1−xMxS with the early 3d transition metal impurities (M: Ti, V and Cr).

Original languageEnglish
Pages (from-to)2600-2608
Number of pages9
JournalJournal of the Physical Society of Japan
Issue number7
Publication statusPublished - 1995 Jul



  • NiRhS
  • XPS
  • charge-transfer type compound
  • magnetic susceptibility
  • nonmetal-metal transition
  • thermal expansion
  • thermoelectric power

ASJC Scopus subject areas

  • Physics and Astronomy(all)

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