Crystal structures of the R3CuSnSe7 (R = La, Ce, Pr, Nd, Sm, Gd, Tb and Dy) compounds

The crystal structures of the R3CuSnSe7 (R = La, Ce, Pr, Nd, Sm, Gd, Tb and Dy) compounds (La3CuSiS7 structure type, space group P6(3), Pearson symbol hP24), were determined by means of X-ray powder diffraction: a 1.07211 (1) nm, c = 0.62770(1) nm, R-I = 0.0613 (La3CuSnSe7); a = 1.06310(2) nm, c = 0.62562(1) nm, R-I = 0.0737 (Ce3CuSnSe7); a = 1.05613(4) nm, c = 0.62532(3) nm, R-I = 0.0964 (Pr3CuSnSe7); a = 1.05002(4) nm, c = 0.62523(2) nm, R-I = 0.0808 (Nd3CuSnSe7); a = 1.03809(2) nm, c = 0.62848(2) nm, R-I = 0.0745 (Sm3CuSnSe7); a = 1.02435(2) nm, c = 0.63409(2) nm, R-I = 0.0834 (Gd3CuSnSe7); a = 1.01894(2) nm, c = 0.63642(2) nm, R-I = 0.0881 (Tb3CuSnSe7); a = 1.01359(3) nm, c = 0.63809(3) nm, R-I = 0.0916 (Dy3CuSnSe7). (C) 2004 Elsevier B.V. All rights reserved.