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arXiv · 1712.06726

Synthesis, Crystal Structure, and Physical Properties of New Layered Oxychalcogenide La2O2Bi3AgS6

Yudai Hijikata·Tomohiro Abe·Chikako Moriyoshi·Yoshihiro Kuroiwa·Yosuke Goto·Akira Miura·Kiyoharu Tadanaga·Yongming Wang·Osuke Miura·Yoshikazu Mizuguchi
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Abstract

We have synthesized a new layered oxychalcogenide La2O2Bi3AgS6. From synchrotron X-ray diffraction and Rietveld refinement, the crystal structure of La2O2Bi3AgS6 was refined using a model of the P4/nmm space group with a = 4.0644(1) Å and c = 19.412(1) Å, which is similar to the related compound LaOBiPbS3, while the interlayer bonds (M2-S1 bonds) are apparently shorter in La2O2Bi3AgS6. The tunneling electron microscopy (TEM) image confirmed the lattice constant derived from Rietveld refinement (c ~ 20 Å). The electrical resistivity and Seebeck coefficient suggested that the electronic states of La2O2Bi3AgS6 are more metallic than those of LaOBiS2 and LaOBiPbS3. The insertion of a rock-salt-type chalcogenide into the van der Waals gap of BiS2-based layered compounds, such as LaOBiS2, will be a useful strategy for designing new layered functional materials in the layered chalcogenide family.

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Yudai Hijikata, Tomohiro Abe, Chikako Moriyoshi, Yoshihiro Kuroiwa, Yosuke Goto, Akira Miura, Kiyoharu Tadanaga, Yongming Wang, Osuke Miura, Yoshikazu Mizuguchi. 2017-12-19. Synthesis, Crystal Structure, and Physical Properties of New Layered Oxychalcogenide La2O2Bi3AgS6. https://doi.org/10.7566/jpsj.86.124802

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