A method has been developed to obtain quantitative electron diffraction data up to a value of Q = 20 Å−1 of the modulus of the scattering vector. The experiments were performed on a commercially available transmission electron microscope equipped with a so-called omega energy filter. An analytical multiple scattering correction was applied. The electron diffraction results obtained with amorphous germanium were compared with X-ray and neutron diffraction data and showed good agreement. For an amorphous Ni63Nb37 sample it was shown that it is possible to estimate the multiple scattering intensity without exact knowledge of the sample thickness. This technique was applied to derive the structure factor for electron diffraction of two precursor-derived amorphous Si-C-N ceramics (a-Si24C43N33 and a-Si40C24N36). The results are consistent with corresponding X-ray diffraction data and with an existing structural model for such ceramics.

The structure factor of amorphous germanium was determined using 120 kV electrons, an ß-filter for the elimination of inelastically scattered electrons and a correction procedure for multiple scattering. The structure factor thus obtained is in good accordance to that obtained with X-rays and neutrons, respectively.

From the combination of quantitative electron-diffraction data with X-ray-and neutron-diffraction data (so-called three-beam experiment) the partial structure factors and pair correlation functions of amorphous sputter deposited W 28 O 72 were determined. On the basis of the experimental atomic distances and coordination numbers, and by comparison with crystalline WO 3 , a structural model was developed, which consists of twisted WO 6 octahedra. Reverse Monte Carlo simulation in accordance with the experimental data was performed to verify the results.

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