| Abstract: Two lanthanide coordination compounds of the bidentate betaine derivative 1,5-bis(3-carboxypyri-diniuties)-N-methyl-diethylamine (L), namely, {[La2L4(H2O)2](ClO4)6·6H2O}n (1) and [Nd2L4(DMF)6(H2O)2]2(ClO4)6·4H2O (2) have been prepared and characterized by infrared spectrum (IR) and single crystal X-Ray structure analysis. Both 1 and 2 are crystallized in space group P1 with a=1.4966(3) nm, b=1.5597(4) nm, c=1.9568(4) nm, α=86.776(6)°, β=77.723(7)°, γ=87.168(7)°, Z=2 for 1, and a=1.0408(4) nm, b=1.3541(5) nm, c=2.975(1) nm, α=94.390(8)°, β=91.720(7)°, γ=95.230(4)°, Z=2 for 2, respectively. In 1, pairs of La(Ⅲ) atoms are bridged by two carboxylate groups forming a di-metal core structures which are linked by carboxylatos to a coordination string running parallel to the c axis. In addition, a notable feature in 1 is the existence of (H2O)6 clusters which consist of cyclic (H2O)4 clusters as cores. In 2, the coordination cation is of a carboxylato-bridged tetrakis-carboxylato wheel like di-metal core structure with a pair of carboxylate groups acting in a syn-syn bridging mode and the other acting in chelating/mono atom bridging mode. CCDC: 998597, 1; 998596, 2. |
