Chirality and Polarity Modulation in Semiconductive Zinc(II) Coordination Polymers Containing Thiolate-Based Ligands.

Recently, chiral semiconductors have attracted considerable attention owing to their potential applicability in optoelectronics and spintronics. In this study, homochiral and heterochiral semiconductive Zn(II) coordination polymers [Zn(tbbt)(()-mba)]·solvent (Htbbt = 4,4'-thiobisbenzenethiol, mba = methylbenzylamine, = , , ) were systematically synthesized. Single-crystal X-ray diffraction analyses revealed that and ( = Kwansei Gakuin framework), of type [Zn(tbbt)(()-mba)]·()-mba, obtained from enantiopure ()-mba and ()-mba isomers, exhibited chiral-nonpolar homochiral one-dimensional (1D) structures with mba lattice solvents, comprising left- and right-handed helical chains, respectively. Conversely, when using ()-mba, two heterochiral 1D architectures were obtained depending on synthetic temperature and solvent. Specifically, of type [Zn(tbbt)(()-mba)]·()-mba·HO exhibited an achiral-nonpolar heterochiral 1D structure with ()-mba and HO lattice solvents, containing alternately aligned left-handed helical chains with ()-mba and right-handed helical chains with ()-mba. Conversely, with the formula [Zn(tbbt)(()-mba)] formed an achiral-polar assembly without mba lattice solvents. This structure is composed of zigzag chains with either ()-mba or ()-mba in a heterochiral arrangement. Time-resolved microwave conductivity measurements and first-principles calculations revealed that a series of Zn(II) coordination polymers exhibited photoconductivity originating from the Zn-thiolate-based skeleton. Furthermore, by exchanging the mba ligands coordinated to 1D Zn-thiolate chains, a reversible structural conversion accompanied by chirality and polarity variation was achieved.