Selenium Oxoanion Compounds of Palladium(II)

2007-07-09T00:00:00Z (GMT) by Jie Ling Thomas E. Albrecht-Schmitt
Three new palladium compounds, PdSeO3, PdSe2O5, and Na2Pd(SeO4)2, containing selenium oxoanions of both Se(IV) and Se(VI) have been prepared under mild hydrothermal conditions. PdSe2O5 and Na2Pd(SeO4)2 both possess one-dimensional structures. Within the structure of PdSe2O5, [PdO4] square planar building blocks are joined together through diselenite, Se2O52-, anions, and form a zigzag chain along the c axis. In Na2Pd(SeO4)2, [PdO4] units are connected by two selenate, SeO42-, anions, and extend along the a axis to form a [Pd(SeO4)2]2- chain. Na+ cations reside in the space between the [Pd(SeO4)2]2- chains and act as counter cations. Unlike above two compounds, PdSeO3 exhibits a layered structure. In the structure of PdSeO3, [PdO4] units are connected to each other by corner-sharing and form a zigzag chain along the b axis. The chains are further joined together by tridentate selenite, SeO32-, anions to form layers in the [ab] plane that stack along the c axis. Crystallographic data:  (193 K; Mo Kα, λ = 0.71073 Å):  PdSeO3, monoclinic, space group P21/m, a = 3.8884(5) Å, b = 6.4170(8) Å, c = 6.1051(7) Å, β = 96.413(2)°, V = 151.38(3) Å3, Z = 2; PdSe2O5, monoclinic, space group C2/c, a = 12.198(2) Å, b = 5.5500(8) Å, c = 7.200(1) Å, β = 107.900(2)°, V = 463.8(1) Å3, Z = 4; Na2Pd(SeO4)2, triclinic, space group P1̄, a = 4.9349(11) Å, b = 5.9981(13) Å, c = 7.1512 (15) Å, α = 73.894(4)°, β = 86.124(4)°, γ = 70.834(4)°, V = 192.03(7) Å3, Z = 1.