Kussainova, Ardak M.Akselrud, Lev G.Suen, Nian-TzuVoss, LeonardStoyko, StanislavBobev, Svilen2017-12-212017-12-212016-01-01Ardak M. Kussainova, Lev G. Akselrud, Nian-Tzu Suen, Leonard Voss, Stanislav Stoyko, Svilen Bobev, Synthesis, crystal and electronic structure of the quaternary sulfides Ln2CuMS5 (Ln=La, Ce; M=Sb, Bi), In Journal of Solid State Chemistry, Volume 233, 2016, Pages 269-27600224596https://www.sciencedirect.com/science/article/pii/S0022459615302280http://nur.nu.edu.kz/handle/123456789/2979Abstract The series of quaternary sulfides with general formula Ln2CuMS5 (Ln=La, Ce; M=Sb, Bi) have been synthesized by solid-state reactions. Three representative members have been structurally characterized by single-crystal X-ray diffraction. La2CuSbS5 crystallizes in a new structure type (space group Ima2 (no. 46), Z=4, a=13.401(2)Å, b=7.592(1)Å, c=7.598(1)Å, V=773.1(3)Å3). The bismuth analogs of composition La2CuBiS5 and Ce2CuBiS5 crystallize with the La2CuInSe5 structure type (space group Pnma (no. 62), Z=4). Lattice parameters for La2CuBiS5: a=11.9213(5)Å, b=3.9967(2)Å, c=17.0537(8)Å, V=812.56(7)Å3; lattice parameters for Ce2CuBiS5: a=11.9179(15)Å, b=3.9596(5)Å, c=16.955(2)Å, V=800.13(17)Å3). The similarities and the differences between the two structures are discussed. Electronic structure calculations for La2CuSbS5 and La2CuBiS5 are also presented; they suggest semiconducting behavior with energy gaps exceeding 1.7eV.enQuaternary chalcogenidesCrystal structureElectronic structureRare-earth metalsArticlePublished by Elsevier Inc.