Materials Data on Y5(SiB4)2 by Materials Project

Abstract

Y5Si2B8 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. there are two inequivalent Y sites. In the first Y site, Y is bonded in a 12-coordinate geometry to nine B and three equivalent Si atoms. There are a spread of Y–B bond distances ranging from 2.64–2.97 Å. There are one shorter (3.07 Å) and two longer (3.13 Å) Y–Si bond lengths. In the second Y site, Y is bonded to two equivalent B and four equivalent Si atoms to form corner-sharing YSi4B2 octahedra. The corner-sharing octahedral tilt angles are 57°. Both Y–B bond lengths are 2.74 Å. All Y–Si bond lengths are 2.91 Å. There are three inequivalent B sites. In the first B site, B is bonded in a 9-coordinate geometry to four equivalent Y and five B atoms. There are a spread of B–B bond distances ranging from 1.76–1.83 Å. In the second B site, B is bonded in a 3-coordinate geometry to six equivalent Y and three B atoms. The B–B bond length is 1.85 Å. In the third B site, B is bonded in a 9-coordinate geometry to five Y and four equivalent B atoms. Si is bonded in a 9-coordinate geometry to eight Y and one Si atom. The Si–Si bond length is 2.35 Å.