The atomic pair distribution functions ~PDFs! of four powder samples of YBa2Cu3O61x (x 50.25, 0.45, 0.65, 0.94) at 15 K have been measured by means of pulsed neutron diffraction. The PDF is modeled using a full-profile fitting approach to yield structural parameters. In contrast to earlier x-ray absorption fine structure work we find no evidence of a split apical oxygen site. However, a slightl...

For large-grained samples it is advantageous to perform pairs of neutron diffraction measurements at the same spatial location but rotated 180° around the geometric centre of the gauge volume as a means of minimizing the scatter coming from the random positioning of grains within the gauge volume.

CoSeO(4) has a structure consisting of edge-sharing chains of Co(2+) octahedra which are held together by SeO(4)(2-) tetrahedra via shared oxygen atoms at the edges of the octahedra. DC magnetization measurements indicate a transition to an ordered state below 30 K. Powder neutron diffraction refinements suggest an ordered state with two unique antiferromagnetic chains within the unit cell. Iso...

A current challenge in the field of magnetoelectric multiferroics is to identify systems that allow a controlled tuning of states displaying distinct magnetoelectric responses. Here we show that the multiferroic ground state of the archetypal multiferroic TbMnO3 is dramatically modified by epitaxial strain. Neutron diffraction reveals that in highly strained films the magnetic order changes fro...

Using neutron diffraction and the isotopic substitution technique we have investigated the local structure of liquid chloroform. A strong tendency for polar stacking of molecules with collinear alignment of dipole moments is found. We speculate that these polar stacks contribute to the performance of chloroform as a solvent.

The improvements in the crystal structure refinement program SHELXL have been closely coupled with the development and increasing importance of the CIF (Crystallographic Information Framework) format for validating and archiving crystal structures. An important simplification is that now only one file in CIF format (for convenience, referred to simply as `a CIF') containing embedded reflection ...

The answer is yes. A fundamental limit exists, which is not strongly applicable to individual reflections but to a sufficiently large set of reflections such as any set for structure determination. The limit originates from Poisson statistics which gives a minimum (average) error. The proposed limit of significance and a proposed decrease in significance due to data processing are also tested b...