Posted: July 19, 2010

Insights into the development of superior UVB blocking molecules

(Nanowerk News) A research team in Thailand has investigated the absorption and emission spectra of ultraviolet (UV) B blocking methoxy substituted cinnamates using the symmetry-adapted cluster configuration interaction method.
The finding, reported in The Journal of Chemical Physics ("Absorption and emission spectra of ultraviolet B blocking methoxy substituted cinnamates investigated using the symmetry-adapted cluster configuration interaction method"), provides new insights toward the use of five different substituted positions using the symmetry-adapted cluster which included cis- and trans-isomers of ortho-, meta-, and para-monomethoxy substituted compounds and 2,4,5- ortho-, meta-, para- and 2,4,6- ortho-, para- trimethoxy substituted compounds. The calculated oscillator strengths of the trans-isomers were larger than the respective cis-isomers, which is in accordance with the experimental data.
Dr Supawadee Namuangruk, a researcher at Thailand's National Nanotechnology Center (NANOTEC) Nanoscale Simulation Lab, said, "The calculations provide reliable results and a useful insight into the optical properties of these molecules, and therefore, provide a useful tool for developing UVB blocking compounds with regard to the tuning of the photoabsorption"
"High absorbance, broad absorption peak with small fluorescence quantum yield, and low radiative rate are expected for superior UVB sunscreen. Non-radiative decay back to the initial ground state is also relevant. Therefore, the theoretical study of the relaxation process is important to design the superior UVB blocking molecules" said Dr Supawadee.
Collaborators on this investigation included Kasetsart University and the Institute for Molecular Science, Japan.
Dr Supawadee is currently working on a collaborative research with Ubon Rachathani University in Thailand on the development of efficient Dye Solar Cells (DSC) based on D-D-pi-A Organic Dyes.
Source: NANOTEC