{Na2[Nd4(OX)(BDC)6(H2O)6]} n : A 3-D coordination polymer with hybrid dicarboxylates

The hydrothermal reactions of lanthanide ions, oxalates and benzenedicarboxylate with ratio of 4 : 1 : 8 at 190°C afford the three-dimensional coordination polymer Na₂[Nd₄(OX)(BDC)₆(H₂O)₆] (OX = oxalate and BDC = 1,3-benzenedicarboxylate dianion). Crystal data: C₂₅H₁₈NaNd₂O₁₇ M = 901.86, Triclinic, P 1, a = 10.335(6), b = 11.497(6), c = 12.238(7) Å, α = 93.015(9), β =114.892(8)°, γ = 95.970(10)°, V = 1304.3(12) ų, Z = 2, F(000) = 870, R ₁ = 0.0322, wR ₂ = 0.0683. The central oxalate of the unit cell coordinates with four lanthanides to form a four metal cluster [Ln₄(OX)]. The luminescence spectrum shows weak photoluminescence in infrared and near-infrared.