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The structural state of nanocrystalline samples of expanded graphite is investigated using X-ray diffraction and neutron diffraction analyses. The expanded graphite samples are prepared by a rapid thermal decomposition of intercalation compounds of oxidized graphite based on fluorinated graphite, graphite oxide, and graphite aminofluoride. It is established that the main phase of expanded graphite belongs to the hexagonal crystal system (space group P63/ mmc) and that carbon atoms in the structure occupy the 2 b and 2 c positions. The unit cell parameters and the unit cell volume in the structure of expanded graphite samples are larger than those in the structure of massive graphite. [ABSTRACT FROM AUTHOR]

Magnetic state of the intermetallic TbMn[sub 6]Sn[sub 6] compound was studied by neutron diffraction analysis in external magnetic fields of H = 0, 4, and 5 kOe. Magnetic moments and their orientations were determined for the Tb and Mn sublattices. Magnetic fields higher than 4 kOe were shown to induce spin-reorientational transition at room temperature from the c axis to the basal plane. © 2000 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]