Abstract: | Pale yellow single crystals of Sm2(SeO3)(Se2O5)2 (monoclinic, P21/c, Z = 4, a = 1003.6(2), b = 1022.5(2), c = 1287.3(2) pm, β = 112.3(2)°) were obtained from the reaction of Sm2O3 and SeO2 at 350 °C in a sealed glass ampoule. In the crystal structure both Se2O52? and SeO32? groups connect the Sm3+ ions into layers. Between the layers the lone electron pairs of the anions are located. |