The chain conformation of thin polymer films was investigated via diffuse neutron scattering. The samples consist of blend films of protonated and deuterated polystyrene spin coated onto glass substrates. A variation of the thickness of the blend films in a range of about 41 down to 0.66 times the radius of gyration R g of the chains in the bulk enables the determination of film thickness and confinement effects. With diffuse neutron scattering in a reflection geometry the chain conformation in thin polymer films with film thicknesses less than 20 nanometers could be investigated. With decreasing film thickness d below approximately 6 R g the in-plane dimension of the chains starts to increase which is caused by distortion of the chain conformation along the direction parallel and perpendicular to the surface of the film. This increase is quite significant below d < Rg and can be compared to theoretical predictions and simulations.

The reaction of dilithiobutadiyne (or the corresponding di-Grignard reagent) with various dichlorosilanes and dibromogermanes in THF at room temperature afforded poly[(silylene)diacetylenes] and poly[(germylene)diacetylenes], respectively, in high yields. The polymers have a regular alternating arrangement of diyne and silylene or germylene units. When they are doped with FeCl3, these polymers show conductivity values in the range 10r5-10r3 S-cm'1. The values depend greatly on the electronic character of the substituents bonded to silicon or germanium.

The formation of interlayer transition zones (ITZs) in sputtered Mo/Si multilayer structures was studied by means of cross-section electron microscopy and grazing incidence reflectivity measurements. For the evaluation and calculation of interface effects the multiperiodic design of Mo/Si structure was used. It was found that the thickness asymmetry of ITZs (Mo-on-Si and Si-on-Mo) in Mo/Si multilayer structures depends on the degree of perfection of the crystalline structure of the molybdenum layer. A transition from asymmetrical to symmetrical ITZs with a disordering of the molybdenum crystalline structure was shown. A model for the formation mechanism of asymmetrical ITZs at the different interfaces in Mo/Si multilayer structures is suggested. According to this model, ITZ formation at the Mo-on-Si interface is controlled by the surface diffusion of Si atoms on the growing molybdenum surface. In contrast, ITZ formation at the Si-on-Mo interface is determined by the bulk diffusion of Si atoms in textured molybdenum grain

We show that the accessible range of length scales of structures deduced with ultra small-angle scattering (USAX) experiments can be enlarged by more than one order of magnitude in reflection geometry set-ups. From the analysis of the diffuse scattering without further model assumptions the length scale of the structures is determinable. The method is illustrated by an example of thin blend films of deuterated polystyrene (dPS) and polyparamethylstyrene (PpMS) where mm-structures are recovered. The results are compared to atomic-force microscopy measurements. For a further comparison, USAX data of a water-based dispersion of polymer particles are presented. They illustrate the resolvable length scale of the conventional transmission geometry.

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