title: Spectroscopic study of the authentic emitter of AMPPD chemiluminescence in alkaline aqueous solution.
abstract: To design more effective CIEEL (chemically initiated electron exchange luminescence) systems demands a complete picture of the dynamics of the chemiluminescence, which is often a challenge. In this work, photoluminescence of the methyl m-oxybenzoate anion - the authentic emitter of AMPPD (3-[2-spiroadamantane]-4-methoxy-4-[3-phosphoryloxy]-phenyl-1,2-dioxetane) in aqueous solvent has been studied. Combining the effect of solvent properties, e.g. pH value, and spectroscopic studies employing steady-state and ultrafast time-resolved emission and absorption and (1)H NMR techniques, a novel mechanism is proposed. We conclude that the deviation of emission peaks between chemiluminescence and photoluminescence of the authentic emitter of AMPPD i.e. the methyl m-oxybenzoate anion, in alkaline aqueous solvents is due to its hydrolysis, rather than the hydrogen-bonding effect as has been assumed so far. Besides, the hydrogen-bonding is suggested to play a key role in significantly decreasing the chemiluminescence yield of AMPPD in aqueous solution by shortening the lifetime of the excited authentic emitter to 10 ps order of magnitude - three orders of magnitude shorter than the previously reported value ( approximately 10 ns). These results shed light on the chemiluminescence dynamics of AMPPD and facilitate the design of more effective CIEEL systems.
authors.affiliation: Key Laboratory of Excited-State Processes, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China.
authors.forename: Langping
authors.initials: L
authors.lastname: Tu
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Yifei
authors.initials: Y
authors.lastname: Yang
authors.forename: Bert H
authors.initials: BH
authors.lastname: Bakker
authors.forename: Xianggui
authors.initials: X
authors.lastname: Kong
authors.forename: Albert M
authors.initials: AM
authors.lastname: Brouwer
authors.forename: Wybren J
authors.initials: WJ
authors.lastname: Buma
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
mesh_terms: D000218:Adamantane / Q000031:analogs & derivatives* / Q000737:chemistry; D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D013050:Spectrometry, Fluorescence
chemical_list: C061523:3-(2'-spiroadamantane)-4-methoxy-4-(3''-phosphoryloxy)phenyl-1,2-dioxetane; D000218:Adamantane