A Novel Layer Crystal Structure of Sr(II) Complex based on 2-methyl-1H-imidazole-4,5-dicarboxylate Ligand

Abstract

A layer coordination polymer of [Sr(H₂MIDC)₂(H₂O)₂]_n, (H₃MIDC = 2-methyl-1H-imidazole-4,5-dicarboxylate) has been synthesized and characterized. Single X-ray structural analysis indicates the title compound crystallizes in a monoclinic lattice, P2₁/n with a = 6.902(1) b = 14.469(3), c = 16.641(3) Å, β = 98.58(3)°, Z = 4, V = 1643.2(6) ų, ρ_c = 1.867 g/cm³, F(000) = 928, S = 1.079, R₁ = 0.1346, wR₂ = 0.3892 (CIF file CCDC no. 791212). Crystal structure analysis reveals that Sr²⁺ ion is eight-coordinate and lies in a bicapped tetragonal bipyramid environment with one nitrogen atom and seven oxygen atoms. For the variaties of the ligand’s coordination modes and the bridging oxygen atom in carboxylate group, the structure presents a two-dimensional layer molecular network. This coordination polymer exhibited intense fluorescent emissions in the solid state at room temperature.