| Abstract: | Sm3ClSiO4]2: A Chlorine‐poor Chloride Orthosilicate of Samarium Pale yellow, plate‐like single crystals of Sm3ClSiO4]2 (orthorhombic, Pnma; a = 701.74(8), b = 1800.8(2), c = 626.63(7) pm; Z = 4) are obtained upon the reaction of SmCl3, Sm2O3 and SiO2 (”?Kieselgel”?”?) in 1 : 4 : 6 molar ratios, most advantageously in the presence of substantial amounts of NaCl as fluxing agent, after seven days at 850 °C in evacuated silica ampoules. The B‐type crystal structure (isotypic with e. g. Yb3ClSiO4]2) contains discrete orthosilicate tetrahedra SiO4]4– which form anionic double layers ({(Sm1)2SiO4]2}2–) with (Sm1)3+. These are alternatingly sheethed along 010] with cationic monolayers ({(Sm2)Cl}2+) consisting of (Sm2)3+ and Cl–. Both crystallographically independent Sm3+ cations exhibit coordination numbers of eight (Sm1: 1 Cl + 7 O; Sm2: 2 Cl + 6 O) with respect to the involved electronegative particles. |
