Two zinc coordination polymers with photochromic behaviors and photo-controlled luminescence properties

Two new coordination polymers, [Zn(3-NDI) 0.5 (NDC)(DMF)] n ( 1 ) and {[Zn 1.5 (3-NDI) 0.5 (BDC) 1.5 ]·2.5DMF} n ( 2 ), were synthesized based on naphthalenediimide and aromatic dicarboxylic acids (3-NDI = N , N ′-bis (3-pyridine methyl)-1,4,5,8-naphthalenediimide, H 2 NDC = 1,4-naphthalenedicarboxylic acid, H 2 BDC = terephthalic acid, and DMF = N , N ′-dimethylformamide). Complex 1 is a two-dimensional structure, whereas complex 2 is a three-dimensional structure with a hex topology. Both complexes feature photochromic behaviors, which are proved by single-crystal X-ray diffraction, UV-vis spectroscopy and EPR characterization. Furthermore, both complexes have obvious fluorescence quenching behaviors upon irradiation by using a xenon lamp. Two new coordination polymers, [Zn(3-NDI) 0.5 (NDC)(DMF)] n ( 1 ) and {[Zn 1.5 (3-NDI) 0.5 (BDC) 1.5 ]·2.5DMF} n ( 2 ), were synthesized. Both complexes show photochromic behaviors and have obvious fluorescence quenching behaviors upon irradiation.