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Information × Registration Number 0213U001081, 0112U005674 , R & D reports Title Fluorescent chemosensor for monitoring of toxic metals contents in water popup.stage_title Head Svechkarev Denis, Registration Date 15-01-2013 Organization Kharkov National University named after V.N. Karazin popup.description2 Objects of investigation: solvents: methanol; water; cations: Mg2+, Cu2+, Pb2+, Ba2+, Ni2+, Hg2+, Zn2+, Cd2+, Be2+. Fluorescent dyes: 2-(2,5-diphenyloxazol-2-yl)-3-hydroxychromone, 2-(quinolin-2-yl)-3-hydroxychromone, 1,4-bis-(3-hydroxy-4-oxo-4Н-chromen-2-yl)-benzene. Scope of the work: inverstigation of complex multi-band fluorescence spectra as result of the excited-state proton phototransfer reaction; elucidation of correlation between fluorescent properties and thermodynamic parameters of s- and d-elements complexes woth organic ligands - derivatives of 3-hydroxychromone and electronic structure of the xentral atom and ligand molecule, as well as other parameters of microenvironment. Methods of investigation: quantum-chemical calculations, molecular absorption and fluorescence spectroscopy. Investigated heterocyclic derivatives were shown to be capable to form three types of complexes with Hg2+ ions (chelate, "outer" and mixed) possessing different stoichiometry (ML and M2L). 3-Hydroxychromone bearing a 2,5-diphenyloxazole moiety shows high sensitivity to mercury ions, which is characterized with a detection limit lower than the MPC for this metal in drinking water ~10-10 M. Nitrogen atom participation in the mercury ion chelation process in the case of 2-(quinolin-2-yl)-3-hydroxychromone leads to the fluorescence ignition, which is quite unusual for heavy metal complexes. Two-stage proton transfer in bis-flavonol with the formation of ditautomeric form via the intermediate stage of monotautomer is energetically unfavorable. However, the energy difference between the excited normal and ditautomeric forms is quite small, which leaves a possibility for a concerted double proton phototransfer. The investigated compounds are prospective as a basis for in-line sensors constructions for determination of mercury ions in water on a real-time basis. Product Description popup.authors Дерека Б. Колодєзний Д. Свєчкарьов Д. popup.nrat_date 2020-04-02 Close