A novel heterostranded double-helical coordination polymer with chiral channels emitting blue fluorescence

A novel heterostranded double-helical coordination polymer is self-assembly from two flexible ligands, 4-carboxymethylbenzoic acid (H₂L) and 1,1′-(1,4-butanediyl)bis(imidazole) (abbr. as bbi), with Zn²⁺ ion under solvent-thermal condition. The heterostranded double-helix constructs a chiral channel, which is filled by lattice water molecules; the adjacent heterostranded double-helical channels share Zn²⁺ ions to develop into a homochiral helical two-dimensional sheet, and the right- and left-handed chiral sheets further array in an alternating fashion to generate a racemic crystal via van de Waals forces. This coordination polymer emits blue fluorescence in the solid state.