Photochromic Polyoxometalate/Perylenediimide Donor–Acceptor Hybrid Crystals with Interesting Luminescent Properties
Ming‐Hua You, Meng-Hua Li, Yi‐Ming Di, Shuquan Zhang, Mei‐Jin Lin
Abstract
The self-assembly of electron-deficient protonated N, N′-dipyridyltetrachloroperylenediimide (4Cl-DPPDI) and electron-rich polyoxometalate acids HnXM12O40 (POMs; X = P or Si; M = W or Mo) resulted in four isomorphous donor–acceptor hybrid crystals 1–4 with segregated POM anions and one-dimensional racemic hydrogen-bonded 4Cl-DPPDI networks as electron-donor and -acceptor components, respectively. Because of the compact contacts between the POM anions and 4Cl-DPPDI tectons induced by anion−π interactions, besides enhanced photochromism, these four unique isostructural hybrids exhibited unusual room-temperature phosphorescence (RTP) emissions. More interestingly, owing to the facial compact contacts of two racemic 4Cl-DPPDI tectons induced by lone pair−π-assisted π–π interactions, they also showed unprecedented photon upconversion by triplet–triplet annihilation (TTA).