Effect of cation ordering on the electronic and lattice dynamic properties of Ag₂CdGeS₄ polytypes: First-principle calculation

Journal Article · Wed May 01 04:00:00 EDT 2013 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/J.JSSC.2013.02.007· OSTI ID:22306265

Wei, Lei ^[1]; Fan, Weiliu ^[2]; Li, Yanlu ^[3]; Zhao, Xian ^[1]; Yang, Lei ^[1]

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1. State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100 (China)
2. School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)
3. Department of Physics, Universität Paderborn, Paderborn 33095 (Germany)

The electronic and lattice dynamic properties of I₂–II–IV–VI₄ quaternary diamond-like semiconductors have a tight connection with their application in the area of solar cell absorption, thermoelectric conversion and so on. Structural configuration of these compounds is focused in present study, although previous researches always pay close attention to compositional modulation. In this paper, Ag₂CdGeS₄ polytypes (two types of Pna2₁, one type of Pmn2₁) have chosen as the representation to establish the relationship between cation ordering and physiochemical properties based on first-principle theory. The results show that cation arrangement practically affects their electronic and lattice dynamic properties such as bonding strength, band structure as well as their infrared spectrum. Due to different cation arrangement, two types (named model S and model P) of the same space group Pna2₁ demonstrate different properties. For both model P and Pmn2₁ of different space group, their related properties are alike because of similar cation arrangement. With the resulting cationic Born effective charges, the origin of the difference in electronic properties for three types of Ag₂CdGeS₄ can be reasonably explained from the viewpoint of vibrational polarization. - Graphical abstract: First-principle calculations were used to investigate the effect of cation ordering on the electronic and lattice dynamic properties of Ag₂CdGeS₄ polytypes. Highlights: • Structural configuration was focused other than compositional modulation. • Establish the relationship between cation ordering and physicochemical properties. • Explain the reason of different band gap with Born effective charges. • Calculated infrared spectrum can be used to distinguish different polytypes.

• OSTI ID: 22306265
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Vol. 201; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION
BONDING
CATIONS
CONFIGURATION
DIAMONDS
EFFECTIVE CHARGE
INFRARED SPECTRA
ORTHORHOMBIC LATTICES
POLARIZATION
SEMICONDUCTOR MATERIALS
SOLAR CELLS
SPACE GROUPS
THERMOELECTRIC CONVERSION