A new acentric heterometallic inorganic–organic hybrid framework with an unusual {Cd3Na4}n array: NLO and ferroelectric properties

By employing 1,1′-biphenyl-3,3′-dicarboxylic acid (3,3′-H2BPDA) as a bridging ligand, a novel acentric heterometallic inorganic–organic hybrid framework [Cd3Na4(3,3′-BPDA)5(DME)7]·DME (1) has been synthesized. Single crystal X-ray diffraction study reveals that 1 contains an unusual 1D {Cd3Na4}n motif which is further extended into a 2-fold interpenetrating layer by trans-coordinated 3,3′-BPDA2 − ligands. Compound 1 is NLO active with a SHG effect being 0.5 times that of KDP. Besides, it also displays a potential ferroelectric property.