We present theoretical methods and computations of the effects of nanoparticles on nonlinear optical properties of symmetric molecules. We utilize quantum mechanical/molecular mechanics (QM/MM) response methods for calculating electromagnetic properties of molecules interacting with nanoparticles, and we report calculations of the frequency-dependent first hyperpolarizability. The frequency-dependent first hyperpolarizability of (p)-benzenedithiol in the presence of zero, one, or two gold nanoparticles of varying sizes and distances is calculated by DFT/MM. The hyperpolarizability of the molecule depends strongly on the distance between the nanoparticles and the molecule, whereas the size of the nanoparticle is of little importance. We clearly show that metal nanoparticles are able to induce a first hyperpolarizability in symmetric molecules.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films