Effect of isomorphic atom substitution on the lattice parameters and the optical absorption edge of TlGaSe2-TlInSe2 mixed crystals

Gasanly N. M.

JOURNAL OF THE KOREAN PHYSICAL SOCIETY, vol.48, no.5, pp.914-918, 2006 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 48 Issue: 5
  • Publication Date: 2006
  • Journal Name: JOURNAL OF THE KOREAN PHYSICAL SOCIETY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.914-918
  • Keywords: X-ray diffraction, optical absorption, mixed crystals, SINGLE-CRYSTALS, TLGASE2, CHALCOGENIDES, TLINS2
  • Middle East Technical University Affiliated: No

Abstract

The variation of lattice parameters of TlGaSe2-TlInSe2 mixed crystals with composition have been investigated by using of X-ray diffraction technique. For the mixed crystals studied, a structural phase transition (monoclinic to tetragonal) due to atom substitution is observed when the sum of the tetrahedral covalent radii of the Ga(In) and the Se atoms in Ga(In)Se-4 tetrahedra reaches a critical value of about 0.254 nm. From transmission and reflection measurements, the compositional dependence of the indirect energy band gap was revealed.