New quaternary bismuth sulfides: Syntheses, structures, and band structures of AMBiS4 (A = Rb, Cs; M = Si, Ge)

Jiyong Yao, Bin Deng, Donald E Ellis, James A Ibers*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

26 Scopus citations

Abstract

Four new compounds, RbSiBiS4, RbGeBiS4, CsSiBiS4, and CsGeBiS4, have been synthesized by means of the reactive flux method. The isostructural compounds RbSiBiS4, RbGeBiS4, and CsGeBiS4 crystallize in space group P21/c of the monoclinic system with four formula units in cells of dimensions at 153 K of a = 6.4714(4) Å, b = 6.7999(4) Å, c = 17.9058(11) Å, and β = 108.856(1)° for RbSiBiS4, a = 6.5864(4) Å, b = 6.8559(4) Å, c = 17.9810(12) Å, and β = 109.075(1)° for RbGeBiS4, and a = 6.5474(4) Å, b = 6.9282(4) Å, c = 18.8875(11) Å, and β = 110.173(1)° for CsGeBiS4. CsSiBiS4 crystallizes in a different structure type in space group P21/c of the monoclinic system with four formula units in a cell of dimensions at 153 K of a = 9.3351(7) Å, b = 6.9313(5) Å, c = 12.8115(10) Å, and β = 109.096(1)°. The two structure types are closely related and consist of 2∞[MBiS4 -] (M = Si, Ge) layers separated by bicapped trigonal-prismatically coordinated alkali-metal atoms. In each, the M atom is coordinated to a tetrahedron of four S atoms and the Bi atom is coordinated to seven S atoms comprising five close S atoms at the corners of a square pyramid with Bi near the center of the basal plane and the sixth and seventh S atoms further away to complete a distorted monocapped trigonal prism. The optical band gaps of 2.23 eV for RbGeBiS4 and 2.28 eV for CsGeBiS4 were deduced from their diffuse reflectance spectra. From a band structure calculation, the optical absorption for RbGeBiS4 originates from the 2∞[GeBiS4 -] layer. The Ge 4p orbitals, Bi 6p orbitals, and S 3p orbitals are highly hybridized.

Original languageEnglish (US)
Pages (from-to)7094-7099
Number of pages6
JournalInorganic Chemistry
Volume41
Issue number26
DOIs
StatePublished - Dec 30 2002

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Inorganic Chemistry

Fingerprint

Dive into the research topics of 'New quaternary bismuth sulfides: Syntheses, structures, and band structures of AMBiS<sub>4</sub> (A = Rb, Cs; M = Si, Ge)'. Together they form a unique fingerprint.

Cite this