Free –NH2 based Chemo sensors for Fluoride anion Recognition: A Computational Study and its correlation with ExperimentalAuthor(s): Masood Ayoub Kaloo, Bilal Ahmad Bhat, Sheikh Abdul Majid, Mushtaq A. Bhat and Abid Hussain Shalla
In this work, theoretical study on the molecular structure and the absorption spectra of diaminomalenonitrile (DAMN) based derivatives through the density functional theory (DFT) and time-dependent density functional theory (TD-DFT) methods is presented. Recently DAMN-based derivatives have been explored to be highly selective and sensitive for fluoride anion recognition via free –NH2 based recognition site. Anion selectivity can be tuned by the electron push–pull property of substituents at the phenyl para-position. This could be understood with the help of Mulliken charge distribution analysis. From the frontier molecular orbital analysis, it is reasonable to support the proposed outcome of proton transfer (PT) mechanism between F− and free –NH2 fragment of receptor. The result of such events came in the form of intermolecular charge transfer (ICT) enhancement. Absorption spectra of neutral and deprotonated forms of all DAMN-based derivatives were calculated theoretically using 6-311++G (d, p) basis set in DFT/TD-DFT method.