Metal induced enhancement of fluorescence and modulation of two-photon absorption cross-section with a donor-acceptor-acceptor-donor receptor

A symmetric D-π-π′-π-D system has been synthesized that shows high two-photon absorption (TPA) cross-section. In presence of metal ions such as Zn(II), Cd(II), Mg(II) and Ca(II), the TPA cross-section goes down to different extents.