Synthesis, Crystal Structure, and Hirshfeld Surface Analysis of Rubidium trans-Bis(N-methyliminodiacetato)chromate(III)

A new rubidium salt, Rb[Cr(C5H7NO4)(2)] (C5H7NO4 = mida, methyliminodiacetate), was prepared and its molecular structure was determined from synchrotron X-ray data at 173 K. The complex crystallizes in the space group C2/c of the monoclinic system with four mononuclear formula units in a cell with dimensions a = 16.905(3) angstrom, b = 6.483(2) angstrom, c = 13.906(3) angstrom, and beta = 113.95(3)degrees. The Cr atom is located in a center of symmetry with one independent Cr-N bond length of 2.081(2) angstrom and two Cr-O bond lengths of 1.9534(18) and 1.9628(18) angstrom. The Cr(III) ion is coordinated by two N atoms and four O atoms of symmetrical-facial mida ligands, displaying a distorted octahedral geometry. Hirshfeld surface analysis with 2D fingerprint plots revealed that the O center dot center dot center dot H, H center dot center dot center dot H, and O center dot center dot center dot Rb interactions are the main intermolecular interactions. The crystal structure is stabilized by the O center dot center dot center dot H, H center dot center dot center dot H, and O center dot center dot center dot Rb interactions among rubidium cation, the H atoms and the O atoms of carboxylate group from neighboring mida groups.