SYNTHESIS AND CRYSTAL-STRUCTURE OF F-TYPE ERBIUM SESQUISULFIDE, F-ER2S3

Abstract F-Er 2 S 3 crystals were obtained by vapor transport in the presence of foreign atoms (Nb and Cl). The structure of F-Er 2 S 3 was determined by single-crystal X-ray diffraction. F-Er 2 S 3 is monoclinic, space group P2 1 /m, Z = 4, a = 10.901(1) A , b = 3.896(1) A , c = 11.167(1) A , β = 108.804(5)°, R F = 0.046 for 2838 observed reflections with I > 2.5 σ ( I ). All atoms are located at the mirror planes. There are four crystallographically independent erbium atoms in F-Er 2 S 3 , one-half in six coordination, one-quarter in seven coordination and one-quarter in eight coordination by sulfur.