Synthesis And Properties Of Iodoargentate/cuprate Hybrids Directed By Pyrazine Derivatives

Organic-inorganic hybrid materials have attracted much attention in recent years due to their compositional and structural flexibility as well as their potential synergistic effect.Especially,photochromic hybrid materials based on the intermolecular electron transfer are particularly preferred owing to their potential applications in data storage,decoration,displays,and so on.However,most of the photochromic hybrids research mainly employ strong electron acceptors?strong ?-acids?such as viologens/naphthalenediimides derivatives,matched with strong Lewis bases such as oxides and chlorides.Therefore,enrichment of electron donor and acceptor as well as their matching rule,are the key to optimize the material performance and vital significance for practical application.Using a series of alkylated pyrazinium as structural directing agents and electron acceptors,seven iodoargentate/cuprate hybrids were synthesized and characterized by single crystal XRD,PXRD,EPR,UV-vis diffuse reflectance spectra,IR,for systematica exploration of the effect of N-substituent groups on their electron accepting abilities and the structural change of iodoargentate/cuprate hybrids for intermolecular charge transfer?CT?/electron transfer?ET?and chromic performance.The results mainly include the following three aspects: 1)The increase of size of N-alkyl groups on pyrazine tend to reduce intermolecular charge transfer as well as electron transfer and increased bad-gap of hybrids and change photo-/thermo-chromic performance;2)The change of different substituent groups on pyrazine ring can effectively modulate its electron accepting abilities,and lead to the change on CT and band gaps of hybrids;Namely,the band gap of strong electron acceptor is decreased and shows red shift,the band gap of weak electron acceptor is increased and shows blue shift.3)Noteworthy,[Hpyz]₂[Ag₂I₄]·H₂O?1?exhibits versatile photo-and thermo-chromism due to reversible hydration-dehydration,aswell as subsequent occurrence of intermolecular electron-transfer and changes of intermolecular charge transfer states.