Materials Data on Ta2Fe(ReSe4)2 by Materials Project

Abstract

TaReFeSe4TaSe2ReSe2 crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one ReSe2 sheet oriented in the (0, 0, 1) direction; one TaReFeSe4 sheet oriented in the (0, 0, 1) direction; and one TaSe2 sheet oriented in the (0, 0, 1) direction. In the ReSe2 sheet, Re3+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing ReSe6 pentagonal pyramids. All Re–Se bond lengths are 2.54 Å. Se2- is bonded in a distorted T-shaped geometry to three equivalent Re3+ atoms. In the TaReFeSe4 sheet, Ta4+ is bonded to six Se2- atoms to form distorted TaSe6 pentagonal pyramids that share corners with six equivalent FeSe6 octahedra, edges with six equivalent TaSe6 pentagonal pyramids, and a faceface with one FeSe6 octahedra. The corner-sharing octahedral tilt angles are 45°. There are three shorter (2.61 Å) and three longer (2.63 Å) Ta–Se bond lengths. Re3+ is bonded to six Se2- atoms to form distorted ReSe6 pentagonal pyramids that share corners with six equivalent FeSe6 octahedra, edges with six equivalent ReSe6 pentagonal pyramids, and a faceface with one FeSe6 octahedra. The corner-sharing octahedral tilt angles are 45°. There are three shorter (2.51 Å) and three longer (2.65 Å) Re–Se bond lengths. Fe2+ is bonded to six Se2- atoms to form FeSe6 octahedra that share corners with six equivalent TaSe6 pentagonal pyramids, corners with six equivalent ReSe6 pentagonal pyramids, edges with six equivalent FeSe6 octahedra, a faceface with one TaSe6 pentagonal pyramid, and a faceface with one ReSe6 pentagonal pyramid. There are three shorter (2.55 Å) and three longer (2.57 Å) Fe–Se bond lengths. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to three equivalent Re3+ and three equivalent Fe2+ atoms to form distorted SeFe3Re3 pentagonal pyramids that share corners with three equivalent SeTa3Fe3 pentagonal pyramids and edges with nine SeFe3Re3 pentagonal pyramids. In the second Se2- site, Se2- is bonded to three equivalent Ta4+ and three equivalent Fe2+ atoms to form a mixture of distorted corner and edge-sharing SeTa3Fe3 pentagonal pyramids. In the third Se2- site, Se2- is bonded in a 3-coordinate geometry to three equivalent Ta4+ atoms. In the fourth Se2- site, Se2- is bonded in a distorted T-shaped geometry to three equivalent Re3+ atoms. In the TaSe2 sheet, Ta4+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing TaSe6 pentagonal pyramids. All Ta–Se bond lengths are 2.61 Å. Se2- is bonded in a 3-coordinate geometry to three equivalent Ta4+ atoms.