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Experimental techniques using Bragg diffraction may elucidate electronic and magnetic properties of ferric ions in multiferroic ScFeO3 that are puzzling. A collinear magnetic motif of dipole moments is not expected for s-state ions with an acentric parent (paramagnetic) structure, because single-site anisotropy is negligible and antisymmetric exchange interactions promote an inhomogeneous magnetic motif. However, current indications are that ScFeO3 supports G-type antiferromagnetism, with an unknown moment direction, which implies that ferric ions are not in the high-spin 6S state. It is argued that significant insight on these open questions can be achieved by confronting experimental data with calculated structure factors for resonant x-ray and magnetic neutron Bragg spots, and we report results for G-type antiferromagnetism allowed by the corundum-like parent R3c structure. Calculated structure factors include Dirac multipoles that are time-odd and parity-odd, e.g., dipoles that are often called anapoles or toroidal moments.
The effects of strain on a film of mulitferroic GdMnO3 are investigated using both magnetometry and magneto-optic spectroscopy. Optical spectra, in the energy range 1.5eV - 3.5eV, were taken in Faraday geometry in an applied magnetic field and also a
The lacunar spinel GeV4S8 undergoes orbital and ferroelectric ordering at the Jahn-Teller transition around 30 K and exhibits antiferromagnetic order below about 14 K. In addition to this orbitally driven ferroelectricity, lacunar spinels are an inte
The magnetic and dielectric properties under high magnetic fields are studied in the single crystal of Cu3Mo2O9. This multiferroic compound has distorted tetrahedral spin chains. The effects of the quasi-one dimensionality and the geometrical spin fr
Strong interplay of fundamental order parameters in complex oxides are known to give rise to exotic physical phenomena. The 4d transition metal oxide SrRhO3 has generated much interest, but advances have been hindered by difficulties in preparing sin
We have studied NpPdSn by means of the heat capacity, electrical resistivity, Seebeck and Hall effect, $^{237}$Np M{o}ssbauer spectroscopy, and neutron diffraction measurements in the temperature range 2-300 K and under magnetic fields up to 14 T. Np