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• A MOF based on electron-deficient naphthalene diimide dye is prepared. • The anion–π interactions between two-dimensional network and W6O192– is observed. • Complex 1 exhibits eye-detectable fast-responsive reversible photochromism and photoresponsive luminescence. • Photoinduced electron-transfer produces NDI radicals and W5+ species. Metal-organic frameworks that contain photoactive organic ligands or photoactive inorganic components are an emerging class of multifunctional hybrid materials that in recent years has gradually become an ideal platform for building photochromic complexes. In this paper, a metal-organic framework based on naphthalene diimide (NDI) ligand with Lindqvist-type W 6 O 19 2– polyanions, [Ce 2 (BINDI) (DMF) 8 ]·[W 6 O 19 ] (1), (H 4 BINDI = N, N '-bis(5-isophthalic acid)-1,4,5,8-naphthalene diimide) was synthesized and systematically characterized. It displays a cationic two-dimensional grid coordination network, featuring anion–π interactions between W 6 O 19 2– and expanded π–electron deficient naphthalene diimide (NDI) moieties. Moreover, because of the presence of electron-deficient NDI moieties and photoactive W 6 O 19 2–, this complex exhibits fast responsive reversible photochromism and photoresponsive tunable luminescence. UV–Vis, IR, PXRD, EPR, and XPS spectral studies indicate that the obviously photochromic phenomenon of complex 1 is derived from photoinduced electron-transfer form NDI radicals and W5+ species. [Display omitted]. [ABSTRACT FROM AUTHOR]

• Two isomeric metal-organic frameworks are prepared based on naphthalenediimide and naphthalenedicarboxylic acid. • Complexes 1 and 2 exhibit different photochromism and photocontrolled luminescence upon UV–Vis light irradiation. • Noncovalent interactions play an important role in the photochromic properties of MOFs. As a class of special type materials, photochromic metal-organic frameworks (MOFs) have attracted extensive attention because their usually show interesting color changes and coupled with the variation of some chemical and physical properties under light irradiation. In order to study the effect of secondary building on the photochromism of MOFs, two isomeric naphthalenediimide-based MOFs with different secondary building linkers, namely [Zn 2 (DPNDI)(2,6-NDC) 2 ] (1) and [Zn 2 (DPNDI)(1,4-NDC) 2 ] (2) (DPNDI = N, N '-di(3-pyridyl)-1,4,5,8-naphthalenediimide, 1,4-H 2 NDC = 1,4-naphthalenedicarboxylic acid, 2,6-H 2 NDC = 2,6-naphthalenedicarboxylic acid), were synthesized via solvothermal reaction and the structure were characterized by single-crystal X-ray diffraction, IR and TGA. Owing to the different C H···π interactions between the naphthalene moieties of dicarboxylic acid and electron-deficient DPNDI ligand, they showed different photochromic behaviors and photocontrolled luminescence upon ultraviolet-visible irradiation. Specifically, complex 2 was photochromic but complex 1 was not. The difference can be ascribed to the larger C H···π interaction in complex 1 than in complex 2. This work is expected to provide a new perspective for designing novel photochromic MOF materials Two isomeric naphthalenediimide-based MOFs with different secondary building linkers have been prepared, which exhibit different photochromic behaviors and photocontrolled luminescence upon ultraviolet-visible irradiation. [Display omitted] [ABSTRACT FROM AUTHOR]