Novel donor-acceptor triads of starburst D-A-A type incorporating electron deficient triazine moiety
as a non-conjugating π-spacer/acceptor with two acceptor/anchoring arms comprising of cyanoacetic
acid (DTP-CYA), rhodanine-3-acetic acid (DTP-RHA), barbituric acid (DTP-BA) or thiobarbituric
acid (DTP-TBA) linked to triazine core via a phenyl bridge have been synthesized. Diphenylamine is
used as the donor moiety and the role of the π-spacer on the absorption spectra and other electronic
properties were studied. All the compounds were tested for their non-linear optical properties and
determined the non-linear absorption coefficient (β) and non-linear refractive index (n2) in DMF
solutions. Improved non-linear optical properties were obtained when compared to the compounds
with triazine moiety as a non-conjugating π-spacer/acceptor with rhodanine-3-acetic acid (DTOP-RHA),
barbituric acid (DTOP-BA) or thiobarbituric acid (DTOP-TBA) as anchoring/acceptor groups. DTOP
series compounds are in the geometry of the molecule where the phenyl π-bridge and the triazine unit
are coplanar with the arylidne acceptor unit. The enhanced performance may be due to the structural
variants, which expected to improve through bond coupling between the donor and the terminal acceptor
parts of the molecules and all compounds show asymmetry in the electron density due to the basic
donor-acceptor nature of the structure.
Synthesis, Characterization, Absorbance, Fluorescence and Non Linear Optical Properties of Some Donor Acceptor Chromophores