Electronic energy-structure calculations for orthorhombic InI single crystals

Abstract

Electronic and ground-state properties of indium iodide in the orthorhombic TlI-type structure (space group D2h17) are reported. These properties are derived from the one-particle Kohn-Sham equations in the local-density approximation. The ab initio norm-conserving nonlocal pseudopotential of Bachelet, Hamann and Schluter is used. The corresponding calculational technique is described briefly. Analytical expressions for the matrix elements are obtained. Results are presented for the valence and conduction band energies, densities of states, effective masses and charge densities. In terms of these, a consistent explanation of various experimental measurements of InI single crystals has been obtained. Furthermore, by examining the orbital character and the calculated charge densities of various states, the origin of the bonding in indium iodide has been determined.

Specific Features of Content Dependences for Energy Gap in InxTl1-xI Solid State Crystalline Alloys

“…In this study, a band structure for perfect crystal InI is provided, whereby the smallest direct energy gap E (d) g is localized at the point Γ of the Brillouin zone (BZ). However, in the other studies [10,[12][13][14][15], the location of direct energy gap was detected not at Γ point of BZ.…”

“…[10], the band structure calculations of the single crystal InI were performed using the norm-conserving pseudopotential approach and it was concluded that the energy band gap E One of the first ab initio studies of the point defects in the crystal InI, using the Vanderbilt ultrasoft pseudopotentials and exchange-correlation potential within a framework of the Perdew-Burke-Ernzerhof (PBE) parametrization and the generalized gradient approximation (GGA), are presented in Ref. [11].…”

“…[16], the electronic structure of In x Tl l−x I was calculated using the band structure technique described in Refs. [10,12] within the framework of the local density approximation (LDA). The principal BZ dispersion was theoretically calculated by the linear interpolation between the lattice parameters for the extreme binary compounds according to the Vegard rule.…”

The band energy structure of RbKSO_{4} crystals

“…The first-principles calculations of the energy band structure of RbKSO 4 single crystals were performed using the nonlocal norm-conserving pseudopotential method. The computational technique was described in detail in [5,6]. The theoretical details and basic approximations can be summarized as follows.…”

Enhanced Born charges in III-VII,IV-VII2, andV-VII3compounds

“…1͑c͒, InI has a direct band gap on the H line ͑between T and Y points͒, which disagrees with previous calculations that show an indirect band gap. 18,19 On the other hand, indirect band gaps can be seen for InBr and InCl in Figs. 1͑b͒ and 1͑a͒.…”