A frequency average of the complex local-field correction function ͑LFCF͒, G(q,), of electrons in Li metal has been semiempirically determined for 1.12k F рqр2.59k F (k F ϭFermi momentum͒ by fitting experimental dynamic structure factors, S(q,), to jellium S(q,). The range of frequency averaging was between 3 and 4 eV ͑fitting range͒, its position was in the low-frequency region between 3 and 9 eV, depending on q. For qϽ1.6k F , the real part of the semiempirical LFCF, ReG(q,), is consistent with all current theories, when compared with the static LFCF G(q,ϭ0). For qϾ1.6k F , the semiempirical ReG(q,) exhibits a strong increase in values ranging from 1.2 to 2.4 in a manner which has not been predicted by any existing theory. The relation between G(q,0) and the momentum distribution function n(k) is stressed to make contact with a most recently found anomalous behavior of n(k) in Li. ͓S0163-1829͑96͒09647-6͔

The requirements on the radiation source, the monochromator/mirror, the diffractometer, and the crystal dispersive analyzer for an optimum instrumentation dedicated to high resolution resonant inelastic scattering experiments are formulated. The possibility for the application of dispersion compensation is stressed. A provisional instrumentation at the HARWI–Compton beamline is described and test measurements of the resonant inelastic scattering cross section of Cu for incident photon energies scanning across the K threshold and for scattered photon energies near the Kα1 line are reported. By means of model calculation the important role of correct absorption correction of resonant inelastic scattering data is emphasized.

We report on the measurement of the three-dimensional electron momentum density ͑EMD͒ of a 22 nm Cu/22 nm Ni sandwich foil and of a Cu 0.50 Ni 0.50 alloy film with the same thickness, which was obtained from an identical sandwich by interdiffusion. The EMD's were measured by coincident detection of a Compton scattered photon with its recoil electron. The experiments were performed at the High-Energy beamline of the European Synchrotron Radiation Facility. The experimentally observed small change of the EMD due to alloying is reproduced by the Korringa-Kohn-Rostoker coherent-potential approximation scheme ͓Benedek et al.

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Recently established collaborative structural genomics programs aim at significantly accelerating the crystal structure analysis of proteins. These large-scale projects require efficient data management systems to ensure seamless collaboration between different groups of scientists working towards the same goal. Within the Berlin-based Protein Structure Factory, the synchrotron X-ray data collection and the subsequent crystal structure analysis tasks are located at BESSY, a third-generation synchrotron source. To organize file-based communication and data transfer at the BESSY site of the Protein Structure Factory, we have developed the web-based BCLIMS, the BESSY Crystallography Laboratory Information Management System. BCLIMS is a relational data management system which is powered by MySQL as the database engine and Apache HTTP as the web server. The database interface routines are written in Python programing language. The software is freely available to academic users. Here we describe the storage, retrieval and manipulation of laboratory information, mainly pertaining to the synchrotron X-ray diffraction experiments and the subsequent protein structure analysis, using BCLIMS.