KBiMS{sub 4} (M=Si, Ge): Synthesis, structure, and electronic structure

Journal Article · Thu Jul 15 00:00:00 EDT 2010 · Journal of Solid State Chemistry

OSTI ID:21421557

Dajiang, Mei ^[1]; Zheshuai, Lin; Lei, Bai ^[1]; Peizhen, Fu; Yicheng, Wu ^[1]

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1. Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)

Two new bismuth sulfides KBiSiS{sub 4} and KBiGeS{sub 4} have been synthesized by means of the reactive flux method. They adopt the RbBiSiS{sub 4} structure type and crystallize in space group P2{sub 1}/c of the monoclinic system. The structure consists of {sup {infinity}}{sub 2}[BiMS{sub 4}{sup -}] (M=Si, Ge) layers separated by bicapped trigonal-prismatically coordinated K atoms. The M atom is tetrahedrally coordinated to four S atoms and the Bi atom is coordinated to a distorted monocapped trigonal prism of seven S atoms. The optical band gap of 2.25(2) eV for KBiSiS{sub 4} was deduced from the diffuse reflectance spectrum. From a band structure calculation, the optical absorption for KBiSiS{sub 4} originates from the {sup {infinity}}{sub 2}[BiSiS{sub 4}{sup -}] layer. The Si 3p orbitals, Bi 6p orbitals, and S 3p orbitals are highly hybridized near the Fermi level. The orbitals of K have no contributions on both the upper of valence band and the bottom of conduction band. - Graphical abstract: Two new bismuth sulfides KBiSiS{sub 4} and KBiGeS{sub 4} have been synthesized and characterized. The figure is the view down [0 1 0] of the crystal structure of KBiSiS{sub 4}.

• OSTI ID: 21421557
• Journal Information: Journal of Solid State Chemistry, Vol. 183, Issue 7; Other Information: DOI: 10.1016/j.jssc.2010.05.003; PII: S0022-4596(10)00192-1; Copyright (c) 2010 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ABSORPTION
BISMUTH SULFIDES
ELECTRONIC STRUCTURE
EV RANGE 01-10
FERMI LEVEL
GERMANIDES
LAYERS
MONOCLINIC LATTICES
POTASSIUM COMPOUNDS
SILICIDES
SPACE GROUPS
SYNTHESIS
ALKALI METAL COMPOUNDS
BISMUTH COMPOUNDS
CHALCOGENIDES
CRYSTAL LATTICES
CRYSTAL STRUCTURE
ENERGY LEVELS
ENERGY RANGE
EV RANGE
GERMANIUM COMPOUNDS
SILICON COMPOUNDS
SORPTION
SULFIDES
SULFUR COMPOUNDS
SYMMETRY GROUPS