LAUSR

Mononuclear complexes [Pt(ppy)(S∧S)] (1a, S∧S = O,O′-di(cyclohexyl)dithiophosphate (ctp); 2a, S∧S = O,O′-di(butyl)dithiophosphate (btp)) and [Pt(bzq)(S∧S)] (1b, S∧S = ctp; 2b, S∧S = btp) have been prepared by the reaction of precursor complexes [Pt(C∧N)Cl(dmso)], C∧N = deprotonated form of 2-phenylpyrdine (ppy) and 7,8-benzoquinoline (bzq), and potassium salt of S∧S ligands. All complexes were characterized by NMR spectroscopy, and the structure of 2b was further identified by single crystal X-ray determination. Although the complexes are not luminescent in solution at ambient temperature, they become strong emissive materials (bright green) in solid state (at room temperature) with high quantum yields and long lifetimes in the microsecond domain. In frozen glass state or at low temperature (solid state), these complexes become better emissive in relation to room temperature. UV–vis spectra, supported by TD-DFT calculations, indicate that 1ILCT (intraligand charge transfer) predominates over the other tra...