01603nas a2200169   4500008004100000245008200041210006900123260000800192300001600200490000800216520102100224100001901245700001601264700001701280700002401297856011201321       2016                        eng d00aProton-coupled electron transfer in a hydrogen-bonded charge transfer complex0 aProtoncoupled electron transfer in a hydrogenbonded charge trans  cOCT  a10780-107850 v1203 aA proton-coupled electron transfer (PCET) reaction in a hydrogen bonded charge-transfer (CT) complex of 4-([2,2'-bipyridin]-4-yl)phenol (bpy-phenol) with a F- ion has been investigated by ultrafast time-resolved transient absorption spectroscopy. The phenolic receptor molecule, bpy-phenol, binds to the F- ion through a hydrogen bond and senses the F- ion-via the Stokes-shifted CT band. Upon photoexcitation, CT from the phenol residue to the bpy residue promotes proton transfer from the phenol radical cation (ArOH center dot+) to the fluoride ion at ultrafast time scales of <150 fs (instrument response function limited) and 3 ps, separately. The fast and slow proton-transfer times are linked to two different types of hydrogen-bonding networks between the phenol residue and fluoride ion. Crystalline water in the fluoride salt hydrates mediates the proton-transfer reaction. This work demonstrates the participation of a hydrogen-bonded water bridge within a PCET reaction in a water restricted environment.1 aVerma, Sandeep1 aAute, Sunil1 aDas, Amitava1 aGhosh, Hirendra, N.  uhttps://library.ncl.res.in/content/proton-coupled-electron-transfer-hydrogen-bonded-charge-transfer-complex