Silicon-Bridged donor-acceptor compounds: synthesis and nonlinear optical properties

This thesis describes the synthesis and the spectroscopic and nonlinear optical characterization of a large series of donor- and acceptor-substituted diphenylsilanes with the structure DPh-(SiMez).-PhA and fragments thereof. Nonlinear optics (NLO) deals with the interaction of electromagnetic fields (light) with matter so as to generate new electromagnetic fields altered from the incident field with respect to phase, frequency, amplitude or other propagation characteristics. One of the applications involving nonlinear optical phenomena is frequency doubling of near infrared laser light (frequency a) by a nonlinear optical material into blue light. ... Zie: Summery

Silicon based donor-acceptor compounds: Synthesis and nonlinear optical characterization

For many applications involving nonlinear optical phenomena (e.g.frequency doubling) transparency in the visible spectrum is a requirement. We have synthesized silicon-based donoracceptor compounds that are transparent in the visible and have moderate values of the first hyperpolarizability, p, which are measured with Hyper-Rayleigh Scattering (HRS). The spectroscopic properties (UV-VIS) are studied by investigating the influence of the donor and acceptor strength and the chain length on the absorption maxima and λcutoff values. We have studied the spectroscopic properties (UV-VIS and 29Si-NMR) of model compounds with a trimethylsilyl or pentamethyldisilanyl substituted phenyl ring with various donor and acceptor substituents at the paraposition. Out of various acceptors, the perfluorobutylsulfonyl group seems to be promising, because of its strong electron attracting character and the transparency of the sulfon containing DA-compounds. We will therefore focus on these compounds in studies concerning functionalization and incorporation into a polymer matrix