02320nas a2200205   4500008004100000245013500041210006900176260000800245300001400253490000700267520154800274100001801822700003101840700001801871700002201889700002601911700001901937700002601956856013201982       2012                        eng d00aSelective recognition of fluoride and acetate by a newly designed ruthenium framework: experimental and theoretical investigations0 aSelective recognition of fluoride and acetate by a newly designe  cFEB  a4484-44960 v413 a<p>{An effective anion sensor, [Ru-II(bpy)(2)(H2L-)](+) (1(+)), based on a redox and photoactive {Ru-II(bpy)(2)} moiety and a new ligand (H3L = 5-(1H-benzo[d]imidazol-2-yl)-1H-imidazole-4-carboxylic acid), has been developed for selective recognition of fluoride (F-) and acetate (OAc-) ions. Crystal structures of the free ligand, H3L and [1](ClO4) reveal the existence of strong intramolecular and intermolecular hydrogen bonding interactions. The structure of [1](ClO4) shows that the benzimidazole N-H of H2L- is hydrogen bonded with the pendant carboxylate oxygen while the imidazole N-H remains free for possible hydrogen bonding interaction with the anions. The potential anion sensing features of 1(+) have been studied by different experimental and theoretical (DFT) investigations using a wide variety of anions, such as F-, Cl-, Br-, I-, HSO4-, H2PO4-, OAc- and SCN-. Cyclic voltammetry and differential pulse voltammetry established that 1(+) is an excellent electrochemical sensor for the selective recognition kof F- and OAc- anions. 1(+) is also found to be a selective colorimetric sensor for F- or OAc- anions where the MLCT band of the receptor at 498 nm is red shifted to 538 nm in the presence of one equivalent of F- or OAc- with a distinct change in colour from reddish-orange to pink. The binding constant between 1(+) and F- or OAc- has been determined to be logK = 7.61 or 7.88, respectively, based on spectrophotometric titration in CH3CN. The quenching of the emission band of 1(+) at 716 nm (lambda(ex) = 440 nm</p>1 aKundu, Tanaya1 aChowdhury, Abhishek, Dutta1 aDe, Dipanwita1 aMobin, Shaikh, M.1 aPuranik, Vedavati, G.1 aDatta, Anindya1 aLahiri, Goutam, Kumar  uhttps://library.ncl.res.in/content/selective-recognition-fluoride-and-acetate-newly-designed-ruthenium-framework-experimental-0