Materials Data on LaSiAs3 by Materials Project

Abstract

LaSiAs3 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. La3+ is bonded in a 9-coordinate geometry to nine As+2.33- atoms. There are a spread of La–As bond distances ranging from 3.09–3.23 Å. Si4+ is bonded to four As+2.33- atoms to form corner-sharing SiAs4 tetrahedra. There are a spread of Si–As bond distances ranging from 2.33–2.39 Å. There are three inequivalent As+2.33- sites. In the first As+2.33- site, As+2.33- is bonded in a 4-coordinate geometry to four equivalent La3+ and four equivalent As+2.33- atoms. There are two shorter (2.98 Å) and two longer (3.04 Å) As–As bond lengths. In the second As+2.33- site, As+2.33- is bonded in a distorted rectangular see-saw-like geometry to one La3+ and three equivalent Si4+ atoms. In the third As+2.33- site, As+2.33- is bonded to four equivalent La3+ and one Si4+ atom to form a mixture of distorted edge and corner-sharing AsLa4Si trigonal bipyramids.