Paramagnetic Resonance Absorption in Manganese Fluosilicate Diluted with Magnesium Ions

Studies on fine and hyperfine structures of paramagnetic resonance absorption spectra in single crystals of manganese fluosilicate MnSiF 6 ·6H 2 O diluted with Mg ++ ions in several ratios of Mn:Mg=(1:20)∼(1:150) are reported. This crystal, in undiluted state, has one ion in the unit cell. Measurements were made at room temperature and at the wavelength of 3.2 cm. It is concluded that in these diluted crystals, the unit cell contains six inequivalent Mn ++ ions, the surrounding crystalline fields having different orientations respectively, and that each field has the rhombic symmetry ( D =-294 oe., | E |=32 oe.). It should be pointed out that this field is measurably different from that of the crystal diluted with Zn ++ ions, in which the field has the axially symmetry.