Neutron Diffraction Studies of Various Transition Elements

Abstract

Neutron diffraction measurements are reported on a series of transition elements as an investigation into their magnetic structures. Scattering data have been taken for W, Mo, Nb, V, Cr, Mn, and Fe at various temperatures as low as 4.2\ifmmode^\circ\else\textdegree\fi{}K, and these data are interpreted in terms of the magnetic structure existing in the pure metals. For the first four-named elements, no magnetic scattering either coherent or incoherent is found. Cr and $\ensuremath{\alpha}\ensuremath{-}\mathrm{M}\mathrm{n}$ are established as being antiferromagnetic with N\'eel temperatures of 475\ifmmode^\circ\else\textdegree\fi{}K and 100\ifmmode^\circ\else\textdegree\fi{}K, respectively. Paramagnetic scattering has been observed in manganese at room temperature, and the atomic moments determined for Cr and Mn follow the general trend of the Slater-Pauling curve. Magnetic superstructure effects and magnetic disorder scattering were looked for in iron and neither was found.