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DOE OSTI · 1276367

Materials Data on K2Cd2Te3 by Materials Project

Abstract

K2Cd2Te3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are six inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six Te2- atoms. There are a spread of K–Te bond distances ranging from 3.45–3.91 Å. In the second K1+ site, K1+ is bonded in a 5-coordinate geometry to five Te2- atoms. There are a spread of K–Te bond distances ranging from 3.47–3.89 Å. In the third K1+ site, K1+ is bonded in a 7-coordinate geometry to seven Te2- atoms. There are a spread of K–Te bond distances ranging from 3.53–4.27 Å. In the fourth K1+ site, K1+ is bonded in a 6-coordinate geometry to six Te2- atoms. There are a spread of K–Te bond distances ranging from 3.44–3.97 Å. In the fifth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven Te2- atoms. There are a spread of K–Te bond distances ranging from 3.67–4.05 Å. In the sixth K1+ site, K1+ is bonded in a 6-coordinate geometry to six Te2- atoms. There are a spread of K–Te bond distances ranging from 3.51–4.01 Å. There are six inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded to four Te2- atoms to form a mixture of edge and corner-sharing CdTe4 tetrahedra. There are one shorter (2.89 Å) and three longer (2.90 Å) Cd–Te bond lengths. In the second Cd2+ site, Cd2+ is bonded to four Te2- atoms to form a mixture of edge and corner-sharing CdTe4 tetrahedra. There are a spread of Cd–Te bond distances ranging from 2.83–3.10 Å. In the third Cd2+ site, Cd2+ is bonded to four Te2- atoms to form a mixture of edge and corner-sharing CdTe4 tetrahedra. There are a spread of Cd–Te bond distances ranging from 2.85–2.95 Å. In the fourth Cd2+ site, Cd2+ is bonded to four Te2- atoms to form a mixture of edge and corner-sharing CdTe4 tetrahedra. There are a spread of Cd–Te bond distances ranging from 2.81–3.02 Å. In the fifth Cd2+ site, Cd2+ is bonded to four Te2- atoms to form a mixture of edge and corner-sharing CdTe4 tetrahedra. There are a spread of Cd–Te bond distances ranging from 2.87–2.92 Å. In the sixth Cd2+ site, Cd2+ is bonded to four Te2- atoms to form a mixture of edge and corner-sharing CdTe4 tetrahedra. There are a spread of Cd–Te bond distances ranging from 2.81–3.06 Å. There are nine inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to five K1+ and three Cd2+ atoms. In the second Te2- site, Te2- is bonded in a 6-coordinate geometry to four K1+ and two Cd2+ atoms. In the third Te2- site, Te2- is bonded in a 7-coordinate geometry to four K1+ and three Cd2+ atoms. In the fourth Te2- site, Te2- is bonded in a 7-coordinate geometry to five K1+ and two Cd2+ atoms. In the fifth Te2- site, Te2- is bonded to four K1+ and two Cd2+ atoms to form distorted TeK4Cd2 pentagonal pyramids that share a cornercorner with one TeK4Cd3 pentagonal bipyramid, an edgeedge with one TeK4Cd3 pentagonal bipyramid, and an edgeedge with one TeK4Cd2 pentagonal pyramid. In the sixth Te2- site, Te2- is bonded to four K1+ and three Cd2+ atoms to form a mixture of distorted face and edge-sharing TeK4Cd3 pentagonal bipyramids. In the seventh Te2- site, Te2- is bonded to four K1+ and three Cd2+ atoms to form distorted TeK4Cd3 pentagonal bipyramids that share a cornercorner with one TeK4Cd2 pentagonal pyramid, an edgeedge with one TeK4Cd3 pentagonal bipyramid, an edgeedge with one TeK4Cd2 pentagonal pyramid, and faces with two equivalent TeK4Cd3 pentagonal bipyramids. In the eighth Te2- site, Te2- is bonded in a 7-coordinate geometry to four K1+ and three Cd2+ atoms. In the ninth Te2- site, Te2- is bonded in a 6-coordinate geometry to three K1+ and three Cd2+ atoms.

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2020-04-29. Materials Data on K2Cd2Te3 by Materials Project. https://doi.org/10.17188/1276367

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