A one-dimensional coordination polymer (1D CP) [Zn(glu)(4-nvp)] (1) [H₂glu = glutaric acid and 4-nvp = 4-(1-naphthylvinyl)pyridine] with a paddle-wheel unit [Zn₂(O₂CC)₄] exhibits the photosalient effect under UV as well as sunlight irradiation, resembling the popping of popcorn, along with the release of an elusive cyclobutane ligand.

A 2-mercaptobenzoic acid (2-mba) based zigzag one-dimensional coordination polymer (1D CP) [Cd(2,2′-dsb)(4-nvp)(DMF)(H₂O)] (1) [H₂2,2′-dsb = 2,2′-disulfanediyldibenzoic acid (2,2′-dsba) and 4-nvp = 4-(1-naphthylvinyl)pyridine] has been synthesized by a slow diffusion technique and characterized by elemental analysis, infrared spectra, thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD) pattern and single crystal X-ray diffraction (SCXRD) technique. The monomeric ligand 2-mba yields a dimeric 2,2′-dsb ligand via in situ S–S bond formation which leads to the formation of 1D CP. The flexibility of the structure is due to the S–S bond formation which impacts the electrical conductivity and photosensitivity of the compound. The 1D chains undergo gigantic molecular assembly via hydrogen bonding and C–H⋯π and π⋯π interactions to form a three-dimensional (3D) supramolecular architecture.

This frontier article highlights the design strategy and controlling factors that affect the electrical conductivity of 1D coordination polymers.