1. W. Trzebiatowski Institute of Low Temperature and Structure Research Polish Academy of Sciences, P.O. Box 1410, 50-950 Wrocław 2, Poland
2. International Laboratory of High Magnetic Fields and Low Temperatures 53-421 Wrocław, Poland
3. Department of Inorganic Chemistry, Ivan Franko National University of L'viv 790005 L'viv, Ukraine, Devoted to memory of late E. Leyarovsky