Controlling molecular packing via diffusion methods for enhanced photochromic properties in D-A hybrid heterostructures

Donor-acceptor (D-A) hybrid heterostructures, an emerging class of crystalline hybrid complexes composed of semiconducting organic and inorganic components, have attracted much attention as photochromic materials. Among them, photochromic polyoxometalate/naphthalenediimide D-A hybrid heterostructures represent the most investigated ones, whose photochromic properties are strongly dependent on the structures of polyoxometalates and naphthalenediimides. Herein, we reported their photochromic properties are controlled by their moculelar packings, which were achieved by their diffusion methods. Eight polyoxometalate/naphthalenediimide D-A hybrid heterostructures have been synthesized by the combinations of metal salts (ZnSiF6 center dot 6H(2)O or Zn(ClO4)(2)center dot 6H(2)O), heteropoly acid (H3PMo12O40 or H3PW12O40) and N,N-di (4-pyridyl)-1,4,5,8-naphthalene diimide (DPNDI) via two diffusion methods (A and B). Interestingly, single-crystal X-ray diffraction analyses reveal that they belong to three categories of isostructures with layered, sandwich and interpenetrating packing patterns. Their photochromic properties have been carefully investigated, and the impacts of polyoxometalates as well as packing patterns have also been discussed.

Automated summary

The photochromic properties of polyoxometalate/naphthalenediimide D-A hybrid heterostructures are controlled by their molecular packings, with three categories of isostructures identified through single-crystal X-ray diffraction analyses. The impacts of polyoxometalates and packing patterns on their photochromic properties have been carefully investigated and discussed.