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Il-VI WORKSHOP PurposeThe purpose of this Workshop is to bring together the universities and the industrial and governmental communities that work with II-VI materials which include HgCdTe and other IR materials, Il-VI semiconductor alloys used for x-ray and y-ray detectors, ZnSe-based Il-VI photonic materials, and II:VI photorefractive materials. The Workshop aims at advancing the understanding of the physics and chemistry of these materials. Areas of InterestAreas covered include a broad range of disciplines: materials engineering, intrinsio?' and extrinsic defects including doping, surface sciences, manufacturing/processing, electrical, optical, and magneto-optical properties as well as interactions between them. Workshop FormatTo provide more discussion time, the Workshop program will consist of about 50 papers.When appropriate, invited, encouraged, and contributed papers with a common theme will be grouped for presentation and then followed by an extensive discussion period. Scheduled morning and afternoon breaks as well as lunch, provided as part of the workshop fee, can also be used as additional discussion time. To further promote informal discussion and interaction, the first two days will conclude with a wine and: cheese break accompanied by table-top displays from commercial vendors displaying products and services of interest to the community.

Carbon-coated gadolinum and holmium carbide nanocrystallites have been generated using a modification of the Huffman-Krätschmer carbon arc process. Bulk amounts of these particles were isolated from the other by-products using a magnetic field gradient. Transmission electron microscopy revealed the presence of 10–50 nm diameter crystallites coated with numerous graphitic layers. The nanocrystallite phases were identified as Gd2C3 and Ho2C3, respectively, by x-ray and electron diffraction. Magnetization measurements were performed using a superconducting quantum interference device magnetometer between ±5 T at temperatures ranging from 4 to 200 K. The magnetization curves were shown to scale as a function of H/T. The RE3+ sites in RE2C3 have C3 site symmetry. For Gd2C3 the universal curve was fit with a Brillouin function consistent with the Gd3+ free-ion ground-state values of J=7/2 and g=2. The 5I8 Ho3+ free-ion ground state is split, presumably due to a C3 symmetry crystal field. Consequently, for Ho2C3 the Ho3+ free-ion parameters could not be used to fit the experimental data. Empirical fits to the Brillouin function yield a reduced moment of 7.5μB, compared to the free-ion value of 10.6μB. A similarly reduced moment was observed in holmium-containing endohedral fullerenes.