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Published on: July 19, 2019
Proton translocation and electronic relaxation along a hydrogen-bonded molecular wire in a 6-hydroxyquinoline/acetic
1Photophysics Laboratory, Department of Physics, DSB Campus, Kumaun University, Nainital 263 002, Uttarakhand, India. msmehata@yahoo.com
Abstract:
A hydrogen-bonded network formed between 6-hydroxyquinoline (6-HQ) and acetic acid (AcOH) has been characterized using a time-resolved fluorescence technique. In the bridged hydrogen-bonded complex of cis-6-HQ and AcOH, an excited-state reaction proceeds via proton transfer along the hydrogen bond, resulting in a keto-tautomer (within approximately 200 ps) that exhibits large Stokes-shifted fluorescence. The unbridged complex also undergoes excited-state proton transfer, but the Stokes shift is rather smaller.
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