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The temperature dependence of 35 C1 NQR frequencies and the phase transition behaviour of chloroacetanilides (N-[2,6-dichlorophenyl]-2-chloroacetamide, -2,2-dichloroacetamide, -2,2,2-trichloroacetamide) were investigated. The crystal structure determination of N-[2,6-dichlorophenyl]-2-chloroacetamide leads to the following: a = 1893. A bleaching out of several 35 C1 NQR lines at a temperature far below the melting point of the substances was observed. The different types of chlorine atoms (aromatic, chloromethyl) can be distinguished by their temperature coefficients of the 35 C1 NQR frequencies. All the resonances found show normal "Bayer" temperature behaviour.N-[2,6-dichlorophenyl]-2,2-diehloroacetamide shows several solid phases. One stable low temperature phase and an instable high temperature phase (at room temperature) were observed. The different phases were detected by means of 35 C1 NQR spectroscopy and thermal analysis.

Making use of the quartz microgravimetry method allows one to in situ obtain the m vs. t curves simultaneously with the E cor vs. t curves ( m is the weight of a dissolved or deposited substance, t a time period, E cor a corrosion potential), which gives one a chance to determine the corrosion rate and its dependence on the concentration of copper ions and chloride ions in solution to within a good accuracy. The corrosion rate increases with increasing concentration of ions of divalent copper in solution, while an increase in the concentration of chloride ions does not lead to its change. The formation of a salt film of an intermediate compound of univalent copper during the copper dissolution process in solutions diluted with respect to chloride ions (0.1 M NaCl, 0.03 M CuCl 2 ) is discovered experimentally. In the m vs. t curves, the formation of the film manifests itself in the form of an increase in the electrode weight, while the corrosion potential transients reflect but weakly the occurring complex surface conversions. Techniques for the identification of intermediate solid species are proposed. The coefficients of mass transfer with respect to ions of divalent copper are determined. Explanations for variations in the system's behavior following a decrease in the concentration of chloride ions in solution are offered.

The crystal structure of the hydroxylammonium aluminium sulfate dodecahydrate alum, (NH 3 0H)A1(S0 4 ) 2 · 12H 2 0, has been determined from three dimensional neutron diffraction data. The compound crystallizes cubic with a = 12.328(4) Â in the space group Pa3. The (NH 3 OH) + complex around \ jj, the centre of symmetry, is arranged with equal probability over two orientations related to each other by a centre of symmetry. The elastic diffraction experiment gives a space and time-average picture of two orientations obtained by a rotation of the (NH 3 OH) + complex around an axis perpendicular to the Ν -O bond. The positional and thermal parameters have been refíned by full-matrix least-squares analysis to a weighted Ä-value of 1.9%. Disorder in the (S0 4 ) 2complex has been considered and only 3% disorder has been found.