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DOE OSTI · 1746874

Materials Data on Hf(Ti2Se5)2 by Materials Project

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Abstract

HfSe2(TiSe2)4 is trigonal omega-derived structured and crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of one HfSe2 sheet oriented in the (0, 0, 1) direction and four TiSe2 sheets oriented in the (0, 0, 1) direction. In the HfSe2 sheet, Hf4+ is bonded to six equivalent Se2- atoms to form edge-sharing HfSe6 octahedra. All Hf–Se bond lengths are 2.65 Å. Se2- is bonded in a distorted T-shaped geometry to three equivalent Hf4+ atoms. In each TiSe2 sheet, Ti4+ is bonded to six Se2- atoms to form edge-sharing TiSe6 octahedra. There are a spread of Ti–Se bond distances ranging from 2.56–2.61 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted T-shaped geometry to three equivalent Ti4+ atoms. In the second Se2- site, Se2- is bonded in a distorted T-shaped geometry to three equivalent Ti4+ atoms.

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36 MATERIALS SCIENCEcrystal structureHf(Ti2Se5)2Hf-Se-Ti

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2020-05-03. Materials Data on Hf(Ti2Se5)2 by Materials Project. https://doi.org/10.17188/1746874

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