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Materials Data on HfSe3 by Materials Project

HfSe3 crystallizes in the monoclinic P2_1/m space group. The structure is two-dimensional and consists of one HfSe3 sheet oriented in the (0, 0, 1) direction. Hf4+ is bonded in a 8-coordinate geometry to eight Se+1.33- atoms. There are a spread of Hf–Se bond distances ranging from 2.73–2.90 Å. There are two inequivalent Se+1.33- sites. In the first Se+1.33- site, Se+1.33- is bonded in a distorted L-shaped geometry to two equivalent Hf4+ atoms. In the second Se+1.33- site, Se+1.33- is bonded to four equivalent Hf4+ atoms to form a mixture of distorted edge and corner-sharing SeHf4 trigonal pyramids.

36 MATERIALS SCIENCE↗

Materials Data on HfSe2 by Materials Project

HfSe2 is trigonal omega structured and crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of one HfSe2 sheet oriented in the (0, 0, 1) direction. Hf4+ is bonded to six equivalent Se2- atoms to form edge-sharing HfSe6 octahedra. All Hf–Se bond lengths are 2.69 Å. Se2- is bonded in a distorted T-shaped geometry to three equivalent Hf4+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Hf3Se by Materials Project

Hf3Se is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Hf is bonded in a distorted square co-planar geometry to four equivalent Se atoms. All Hf–Se bond lengths are 3.07 Å. Se is bonded to twelve equivalent Hf atoms to form a mixture of corner and face-sharing SeHf12 cuboctahedra.

36 MATERIALS SCIENCE↗