title: Enhancement of phosphorescence and unimolecular behavior in the solid state by perfect insulation of platinum-acetylide polymers.
abstract: Controlling the thermal fluctuations and molecular environment of a phosphorescent polymer backbone is vital to enhancing its phosphorescence intensity in the solid state. Here, we demonstrate enhanced phosphorescence control through a systematic investigation of cyclodextrin-based insulated platinum-acetylide polymers with well-defined coverage areas. Modification of the coverage areas revealed two unprecedented effects of macrocyclic insulation on phosphorescence behavior. First, the insulation of particular areas suppresses the thermal relaxation processes of the triplet species because of the restriction of structural fluctuations. Cyclic insulation fixes a polymer chain and concomitantly enhances the phosphorescence intensity in both the solution and solid states. Second, complete three-dimensional insulation protects the polymer from interactions with other platinum and acetylide units, and even oxygen molecules. Notably, these polymers display identical phosphorescence behaviors in both the solution and solid states, essentially achieving "unimolecular phosphorescence."
authors.affiliation: Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Kyoto, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Masai
authors.forename: Jun
authors.initials: J
authors.lastname: Terao
authors.forename: Satoshi
authors.initials: S
authors.lastname: Makuta
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Tachibana
authors.forename: Tetsuaki
authors.initials: T
authors.lastname: Fujihara
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Tsuji
mesh_terms: D005030:Ethylenes / Q000737:chemistry*; D008163:Luminescent Measurements; D008958:Models, Molecular; D008968:Molecular Conformation; D010984:Platinum / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013696:Temperature
chemical_list: D005030:Ethylenes; D011108:Polymers; D010984:Platinum