Materials Data on ErSF by Materials Project
SFEr is Matlockite structured and crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Er3+ is bonded in a 9-coordinate geometry to five equivalent S2- and four equivalent F1- atoms. There are four shorter (2.79 Å) and one longer (2.83 Å) Er–S bond lengths. All Er–F bond lengths are 2.44 Å. S2- is bonded in a 5-coordinate geometry to five equivalent Er3+ atoms. F1- is bonded to four equivalent Er3+ atoms to form a mixture of distorted corner and edge-sharing FEr4 tetrahedra.