Materials Data on Pr2MgSi4 by Materials Project
MgPr2Si4 crystallizes in the tetragonal I4_1md space group. The structure is three-dimensional. Mg2+ is bonded in a square co-planar geometry to four Si2- atoms. All Mg–Si bond lengths are 2.79 Å. There are two inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded in a 6-coordinate geometry to six Si2- atoms. There are a spread of Pr–Si bond distances ranging from 3.04–3.29 Å. In the second Pr3+ site, Pr3+ is bonded in a 6-coordinate geometry to six Si2- atoms. There are a spread of Pr–Si bond distances ranging from 3.05–3.29 Å. There are four inequivalent Si2- sites. In the first Si2- site, Si2- is bonded in a 6-coordinate geometry to two equivalent Mg2+, two equivalent Pr3+, and two Si2- atoms. There are one shorter (2.37 Å) and one longer (2.38 Å) Si–Si bond lengths. In the second Si2- site, Si2- is bonded in a 6-coordinate geometry to two equivalent Mg2+, two equivalent Pr3+, and two Si2- atoms. There are one shorter (2.37 Å) and one longer (2.39 Å) Si–Si bond lengths. In the third Si2- site, Si2- is bonded in a 8-coordinate geometry to four Pr3+ and four Si2- atoms. There are two shorter (2.49 Å) and one longer (2.89 Å) Si–Si bond lengths. In the fourth Si2- site, Si2- is bonded in a 8-coordinate geometry to four Pr3+ and four Si2- atoms. The Si–Si bond length is 2.85 Å.