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Neutron diffraction and X-ray absorption measurements were carried out for a perovskite ferromagnet, CaMn0.6Ru0.4O3. While a previous X-ray diffraction had shown an orthorhombic Pnma structure, the present neutron diffraction at room temperature provided a better result for monoclinic P21/n. The analysis for the pattern at 4 K was consistent with the ferro- and antiferromagnetic phase separation at low temperatures. An X-ray absorption spectrum at the Ru–K edge showed that the valence of Ru is higher than 4+, which supports the proposed valency effect.

γ-Mn alloys containing Au have been examined by magnetic measurements and X-ray and neutron diffraction experiments. The 9 at% Au alloy has a face centered orthorhombic lattice with a = 3.853, b = 3.794 and c = 3.731 A at 11 K, and shows a non-collinear antiferromagnetic structure with 4 sublattices; the three-axis components of the magnetic moments are as follows: μ a = 0, μ b = 1.10 and μ c = 1.91 μ B . A revised phase diagram for γ-Mn(Au) alloy system with 8–16 at% Au is proposed.

We have made neutron diffraction experiments for Fe 7- x Mn x Ge 6 with x = 2 and 4 and Co 7- x Mn x Ge 6 with x = 3.25, which have the hexagonal hp 13-type structure. It is determined by the Rietvelt analysis for the nuclear reflection that the 1T 1 site is entirely occupied by Mn atoms and the 6T 2 site by Fe or Co atoms and excess Mn atoms. The magnetic reflection of Fe 3 Mn 4 Ge 6 corresponds to the collinear antiferromagnetism with alternating ferromagnetic layers in which the magnetic moments of the 1T 1 and 6T 2 sites are 2.5 and 1.8 μ B /(Mn or Fe) atom, respectively. Magnetic structures of the other alloys are quite complicated.