C.A. van Walree

Photoinduced charge separation in a donor–acceptor functionalized 2,3-diphenylbutadiene: charge transport over a doubly bifurcated π-spacer

By studying photoinduced charge transfer processes in 2-(4-cyanophenyl)-3-(4-N,N-dimethylaminophenyl)-1,3-butadiene it is shown that insertion of branching points in a pi-conjugated pathway has a relatively small effect on the donor-acceptor interaction.

Praseodymium(III) as a sensitizer of gadolinium(III) in YOCl and GdOCl

Abstract The Pr3+ ion is an efficient sensitizer of the Gd3+ sublattice of GdOCl. The 4f5d excited state of Pr3+ transfers efficiently to the 6I levels of Gd3+. In YOCl the 4f5d state of Pr3+ emits in the short-wavelength ultraviolet region (250–300 nm). By using activators, like e.g. Dy3+, in the Gd3+ sublattice efficient energy transfer from Pr3+ to the activator occurs via many Gd3+ transfer steps.

Simulation of polysilane and polysilyne formation and structure

We present Monte Carlo simulations of the formation and structure of polysilanes and polysilyne networks. The simulation technique allows for the investigation of large systems, containing up to 10 000 monomers. Our results show that ring formation is an important factor for both types of materials. For polysilyne networks, a random structure is found incorporating cyclic substructures, linear chains, and branching points.

Langmuir-Blodgett films of poly(isocyanide)s with different sidechains. 2. poly(3-cholesteryl-6-isocyanohexanoate)

A poly(isocyanide), [RNC <]n, with pendant cholesterol side groups forms stable Langmuir-Blodgett (LB) monolayers at the air-water interface. At high surface pressures, the monolayers are spontaneously transformed into bilayer structures. The monolayer was transferred onto various solid substrates to form LB multilayers. FT-IR, ellipsometry and SAXS indicate that in these multilayers the polymer side chains are oriented perpendicular to the substrate surface.