Synthesis and crystal structure of novel samarium coordination polymer derived from sulfonic acid ligand

Abstract The self-assembly of HL (L=[5-(ethoxycarbonyl)-4-phenyl-3,4-dihydropyrimidin-2(1 H )-one-6-yl]methanesulfonate) with Sm(ClO 4 ) 3 ·6H 2 O yielded a 2D coordination polymer {[SmL 3 (H 2 O) 2 ]·4H 2 O} n ( 1 ). Its crystallographic data indicated that it belonged to a triclinic system, space group P -1, a =1.42233(8), b =1.47155(8), c =1.53868(9) nm, α=8.62710(10), β=6.35250(10), y =71.5790(10)°, V =2.7241(3) nm 3 , Z =2, R 1 =0.0693, wR 2 =0.1054. X-ray analysis revealed that the local coordination environment around Sm(III) was a slightly distorted dodecahedron in which Sm center was eight-coordinate geometry with eight oxygen atoms from three sulfonic groups, three carbonyl groups and two aqua ligands. Each L − acted as a bidentate spacer to link two Sm centers, resulted in the formation of a 2D hexagonally grid network. The discrete 2D planes in 1 were assembled into a 3D supramolecular network via strong hydrogen bonds among noncoordinated aqua O atoms, coordinated aqua O atoms, and noncoordinated O atoms of sulfonic groups and carbonyl groups. Furthermore, this metal-organic polymer exhibited strong photoluminescence maximized at 379 nm upon 274 nm excitation in the solid state at room temperature.