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The evolution of the magnetic propagation vector of the magnetically ordered phases of TbMn2O5 has been studied as a function of magnetic field applied parallel to both [010] and [100] axes. The results have been used to construct (H, T) phase diagrams showing the regions of stability of the three distinct phases IC1, C, and IC2 known to exist in zero field. Application of magnetic field along [010] increases the stability range of the commensurate C phase at the expense of the two incommensurate phases IC1 and IC2, whereas applying the field along [100] has the opposite effect. The evolution with field of the magnetic structure of the C phase has been determined from the integrated intensities of sets of magnetic reflections measured with different field values. With the field along [010], there are no significant changes in structure in fields up to 6 T. Applying the field parallel to [100] leads to an apparently continuous increase in the z component of the propagation vector from 0.25 in zero field to ≈0.3 in 6 T. This change is accompanied by increasing ferromagnetic polarisation of the Tb sublattices. Polarised neutron measurements made on the fundamental reflections show that there is no significant ferromagnetic polarisation of any the Mn sublattices in fields of up to 6 T. [ABSTRACT FROM AUTHOR]

The evolution of the magnetic propagation vector of the magnetically ordered phases of TbMn2O5 has been studied as a function of magnetic field applied parallel to both [010] and [100] axes. The results have been used to construct (H, T) phase diagrams showing the regions of stability of the three distinct phases IC1, C, and IC2 known to exist in zero field. Application of magnetic field along [010] increases the stability range of the commensurate C phase at the expense of the two incommensurate phases IC1 and IC2, whereas applying the field along [100] has the opposite effect. The evolution with field of the magnetic structure of the C phase has been determined from the integrated intensities of sets of magnetic reflections measured with different field values. With the field along [010], there are no significant changes in structure in fields up to 6 T. Applying the field parallel to [100] leads to an apparently continuous increase in the z component of the propagation vector from 0.25 in zero field to ≈0.3 in 6 T. This change is accompanied by increasing ferromagnetic polarisation of the Tb sublattices. Polarised neutron measurements made on the fundamental reflections show that there is no significant ferromagnetic polarisation of any the Mn sublattices in fields of up to 6 T. [ABSTRACT FROM AUTHOR]

Presents a study which examined anisotropy in uranium compounds. Description of the neutron method; Experimental results; Discussion.

Presents information on a study that investigated the magnetic ordering of an isotope enriched Gd[sub2]CuO[sub4] single crystal. Experimental procedure; Results and discussion.

Presents a study that focused on magnetization and neutron-diffraction experiments with both polarized and unpolarized neutrons, which were performed on single crystals of La[sub1.8]Sr[sub0.2]NiO[sub4]. Speculation on the low-temperature state; Reason for using polarized neutron diffraction; Evidence for covalency between the nickel and oxygen(2) atoms.

Presents an experimental technique which enabled the components of both the incident and scattered polarization to be determined. Magnetic structure of chromium[sub2]-oxygen[sub3+]; Role of the cryopad in the neutron polarization; Schematic horizontal section of the cryopad which shows the magnetic fields.

Presents a study that examined the magnetization densities in plutonium compounds. Analytical expressions used in determining magnetic moments; Evaluation of plutonium form factor measured in plutonium-iron; Determination of values of the magnetic moment and carbon[sub2] coefficients.

Provides information on a study that measured magnetic form factor of the 5f electrons around the plutonium nucleus using neutrons. Methodology of the study; Results and discussion of the study.