Synthesis, structure and theoretical studies of a new ternary non-centrosymmetric beta-LaGaS{sub 3}

Journal Article · Mon Feb 15 00:00:00 EST 2010 · Journal of Solid State Chemistry

OSTI ID:21372503

Peng, Li; Longhua, Li ^[1]; Ling, Chen ^[1]

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1. State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences Fuzhou, Fujian 350002 (China)

New ternary beta-LaGaS{sub 3} has been synthesized from the stoichiometric mixture of elements by a conventional solid-state reaction at 1100 deg. C and annealed at 820 deg. C. This compound represents a new structure type that crystallizes in a non-centrosymmetric orthorhombic space group Pna2{sub 1} (No.33) with a=10.405(1) A, b=21.984(2) A, c=6.0565(5) A, and Z=12, and features the wavy GaS{sub 4} tetrahedron chains that are separated by La{sup 3+} cations. Detailed structural differences between the title compound and its isomer, monoclinic alpha-LaGaS{sub 3}, are discussed. With the aid of WIEN2k package, the absorption spectra and electronic structures as well as the refractive indexes, absorption coefficients and reflectivities of two types of LaGaS{sub 3} have been calculated. The calculated band gap and the absorption edge of beta-LaGaS{sub 3} agree well with the experimental measurements. And a weak NLO response of beta-LaGaS{sub 3} has been detected. - Graphical abstract: New non-centrosymmeteic ternary lanthanum gallium sulfide, beta-LaGaS{sub 3}, features the wavy GaS{sub 4} tetrahedron chains that are separated by La{sup 3+} cations has been synthesized by a solid state reaction. Such an orthorhombic beta-LaGaS{sub 3} is isomeric with the monoclinic alpha-LaGaS{sub 3}. Detailed structural differences between the title compound and its isomer, monoclinic alpha-LaGaS{sub 3}, are discussed. The absorption spectra and electronic structures of both types of LaGaS{sub 3} have been calculated with the aid of WIEN2k package as well as the refractive indexes, absorption coefficients and reflectivities. The calculated band gap and absorption edge of beta-LaGaS{sub 3} agree well with the experimental measurements. And a weak NLO response of beta-LaGaS{sub 3} has been detected.

• OSTI ID: 21372503
• Journal Information: Journal of Solid State Chemistry, Vol. 183, Issue 2; Other Information: DOI: 10.1016/j.jssc.2009.11.030; PII: S0022-4596(09)00559-3; Copyright (c) 2009 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
ABSORPTION SPECTRA
ANNEALING
CATIONS
ELECTRONIC STRUCTURE
GALLIUM SULFIDES
LANTHANUM IONS
LANTHANUM SULFIDES
MONOCLINIC LATTICES
ORTHORHOMBIC LATTICES
REFLECTIVITY
REFRACTIVE INDEX
SPACE GROUPS
SYNTHESIS
TEMPERATURE RANGE 1000-4000 K
CHALCOGENIDES
CHARGED PARTICLES
CRYSTAL LATTICES
CRYSTAL STRUCTURE
GALLIUM COMPOUNDS
HEAT TREATMENTS
IONS
LANTHANUM COMPOUNDS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
SORPTION
SPECTRA
SULFIDES
SULFUR COMPOUNDS
SURFACE PROPERTIES
SYMMETRY GROUPS
TEMPERATURE RANGE