One-dimensional magnetic fluctuations in the spin-2 triangular lattice \alpha-NaMnO2 (2009)
Stock, C., Chapon, L. C., Adamopoulos, O., Lappas, A., Giot, M., Taylor, J. W., ...
The S=2 anisotropic triangular lattice alpha-NaMnO2 is studied by neutron inelastic scattering. Antiferromagnetic order occurs at T ~ 45 K with opening of a spin gap. The spectral weight of the...
Magnetic correlations in YBaCo4O7 probed by single-crystal neutron scattering (2009)
Manuel, P., Chapon, L. C., Radaelli, P. G., Zheng, H., Mitchell, J. F.
We have studied the frustrated system YBaCo4O7 generally described as an alternating stacking of Kagome and triangular layers of magnetic ions on a trigonal lattice, by single crystal neutron...
Multiferroicity and spiral magnetism in FeVO$_4$ with quenched Fe orbital moments (2008)
Daoud-Aladine, A., Kundys, B., Martin, C., Radaelli, P. G., Brown, P. J., Simon, C., ...
FeVO$_4$ has been studied by heat capacity, magnetic susceptibility, electric polarization and single crystal neutron diffraction experiments. The triclinic crystal structure is made of...
Radaelli, P. G., Vecchini, C., Chapon, L. C., Brown, P. J., Park, S., Cheong, S-W.
We have determined the magnetic structure of the low-temperature incommensurate phase of multiferroic YMn2O5 using single-crystal neutron diffraction. By employing corepresentation analysis, we have...
Chapon, L. C., Stock, C., Radaelli, P. G., Martin, C.
The weakly interacting S=1/2 dimers system Sr3Cr2O8 has been investigated by powder neutron diffraction and inelastic neutron scattering. Our data reveal a structural phase transition below room...
A Neutron diffraction study of multiferroics RMn2O5 (2008)
Radaelli, P. G., Chapon, L. C.
The magnetic properties of RMn2O5 multiferrroics as obtained by unpolarized and polarized neutron diffraction experiments are reviewed. We discuss the qualitative features of the magnetic phase...
Radaelli, P. G., Chapon, L. C., Daoud-Aladine, A., Vecchini, C., Brown, P. J., Chatterji, T., ...
We employ neutron spherical polarimetry to determine the nature and population of the coexisting antiferromagnetic domains in multiferroic YMn2O5. By applying an electric field, we prove that...
The commensurate phase of multiferroic HoMn2O5 studied by X-ray magnetic scattering (2008)
Beutier, G., Bombardi, A., Vecchini, C., Radaelli, P. G., Park, S., Cheong, S-W., ...
The commensurate phase of multiferroic HoMn2O5 was studied by X-ray magnetic scattering, both off resonance and in resonant conditions at the Ho-L3 edge. Below 40 K, magnetic ordering at the Ho sites...
Capogna, L., Martinelli, A., Francesconi, M. G., Radaelli, P. G., Carvajal, J. Rodriguez, Cabeza, O., ...
The crystal and magnetic structure of (La0.70Ca0.30)(CryMn1-y)O3 for y = 0.70, 0.50 and 0.15 has been investigated using neutron powder diffraction. The three samples crystallize in the Pnma space...
Wawrzynska, E., Coldea, R., Wheeler, E. M., Sorgel, T., Jansen, M., Ibberson, R. M., ...
We report a high-resolution neutron diffraction study of the crystal and magnetic structure of the orbitally-degenerate frustrated metallic magnet AgNiO2. At high temperatures the structure is...
Brown, P. J., Chatterji, T., Radaelli, P. G.
Precise magnetic structures of RMn2O5, with R= Y, Ho, Bi in the commensurate/ferroelectric regime, have been determined by single-crystal neutron diffraction. For each system, the integrated...
Orbital degeneracy removed by charge order in triangular antiferromagnet AgNiO2 (2007)
Wawrzynska, E., Coldea, R., Wheeler, E. M., Mazin, I. I., Johannes, M. D., Sorgel, T., ...
We report a high-resolution neutron diffraction study on the orbitally-degenerate spin-1/2 hexagonal antiferromagnet AgNiO2. A structural transition to a tripled unit cell with expanded and...
Structural anomalies at the magnetic transition in centrosymmetric BiMnO$_3$ (2007)
Montanari, E., Calestani, G., Righi, L., Gilioli, E., Bolzoni, F., Knight, K. S., ...
The structural properties of BiMn$O_3$ were determined from neutron powder diffraction data as a function of temperature and magnetic field. The structure at all temperatures was found to be...
Baier, J., Steffens, P., Schumann, O., Kriener, M., Stark, S., Hartmann, H., ...
The magnetoelastic coupling in Ca$_{1.8}$Sr$_{0.2}$RuO$_4$ and in Ca$_{1.5}$Sr$_{0.5}$RuO$_4$ has been studied combining high-resolution dilatometer and diffraction techniques. Both compounds exhibit...
Bozin, E. S., Schmidt, M., DeConinck, A. J., Paglia, G., Mitchell, J. F., Chatterji, T., ...
The detailed evolution of the magnitude of the local Jahn-Teller (JT) distortion in La_{1-x} Ca_x Mn O_3 is obtained across the phase diagram for 0 < x < 0.5 from high quality neutron diffraction...
Structural phase transition and magnetism in hexagonal srmno (2006)
Daoud-Aladine, A., Martin, C., Chapon, L. C., Hervieu, M., Knight, K. S., Brunelli, M., ...
The structural and magnetic properties of the hexagonal four-layer form of SrMnO$_3$ have been investigated by combining magnetization measurements, electron diffraction and high-resolution...
Symmetry constraints on the electrical polarization in novel multiferroic materials (2006)
Radaelli, P. G., Chapon, L. C.
The symmetry conditions for the development of a macroscopic electrical polarization as a secondary order parameter to a magnetic ordering transition, and the constraints on the direction of the...
Non-collinear long-range magnetic ordering in HgCr2S4 (2006)
Chapon, L. C., Radaelli, P. G., Hor, Y. S., Telling, M. T. F., Mitchell, J. F.
The low-temperature magnetic structure of \HG has been studied by high-resolution powder neutron diffraction. Long-range incommensurate magnetic order sets in at T$_N\sim$22K with propagation vector...
Competing magnetic interactions in the extended Kagome system YBaCo4O7 (2006)
Chapon, L. C., Radaelli, P. G., Zheng, H., Mitchell, J. F.
YBaCo4O7 belongs to a new class of geometrically frustrated magnets like the pyrochlores, in which Co-spins occupy corners of tetrahedra. The structure can be viewed as an alternating stacking of...
The preparation and structures of hydrogen ordered phases of ice (2006)
Salzmann, C.G., Radaelli, P.G., Hallbrucker, A., Mayer, E., Finney, J.L.
Two hydrogen ordered phases of ice were prepared by cooling the hydrogen disordered ices V and XII under pressure. Previous attempts to unlock the geometrical frustration in hydrogen-bonded...
Neutron texture analysis on GEM at ISIS (2006)
Kockelmann, W, Chapon, L C, Radaelli, P G
Texture analysis by time-of-flight neutron diffraction, carried out on a multidetector instrument, requires just a few sample orientations. Moreover, on a diffractometer like GEM at ISIS with...
Structural phase transition and magnetism in hexagonal SrMnO3 (2006)
Daoud-Aladine, A, Martin, C, Chapon, L C, Hervieu, M, Knight, K S, Brunelli, M, ...
Ferroelectricity induced by acentric spin-density waves in YMn$_2$O$_5$ (2005)
Chapon, L. C., Radaelli, P. G., Blake, G. R., Park, S., Cheong, S-W.
The commensurate and incommensurate magnetic structures of the magnetoelectric system YMn$_{2}$O$_{5}$, as determined from neutron diffraction, were found to be spin-density waves lacking a global...
Spin structure and magnetic frustration in multiferroic RMn2O5 (R = Tb, Ho, Dy) (2005)
Blake, G. R., Chapon, L. C., Radaelli, P. G., Park, S., Hur, N., Cheong, S-W., ...
We have studied the crystal and magnetic structures of the magnetoelectric materials RMn2O5 (R = Tb, Ho, Dy) using neutron diffraction as a function of temperature. All three materials display...
Magnetic order and lattice anomalies in the J1-J2 model system VOMoO4 (2005)
Bombardi, A, Chapon, L C, Margiolaki, I, Mazzoli, C, Gonthier, S, Duc, F, ...
High-resolution x-ray and neutron powder-diffraction measurements were performed on polycrystalline VOMoO4. Below .40 K the system orders in a simple Néel antiferromagnetic state spropagation vector...
Structural properties of Ca§2§-§xSr§xRuO§4. (2005)
Schumann, O., Steffens, P., Müller, R., Andre, G., Radaelli, P.G., Adelmann, P., ...
Physik seit Albert Einstein : 69.Jahrestagung der DPG, Berlin, 4.-9.März 2005
Argyriou, D. N., Milne, C. J., Aliouane, N., Radaelli, P. G., Chapon, L. C., Chemseddine, A., ...
We have used electron and neutron powder diffraction to elucidate the structural properties of superconducting \NaD. Our measurements show that our superconducting sample exhbits a number of...
Spin singlet formation in MgTi2O4: Evidence of a helical dimerization pattern (2004)
Schmidt, M, Ratcliff, W, Radaelli, P G, Refson, K, Harrison, N M, Cheong, S W
The transition-metal spinel MgTi2O4 undergoes a metal-insulator (M-I) transition on cooling below TMI = 260 K. A sharp reduction of the magnetic susceptibility below TMI suggests the onset of a...
Spin singlet formation in MgTi$_2$O$_4$: evidence of a helical dimerization pattern (2003)
Schmidt, M., Ratcliff II, W., Radaelli, P. G., Refson, K., Harrison, N. M., Cheong, S. W.
The transition metal spinel MgTi$_2$O$_4$ undergoes a metal-insulator transition on cooling below $T_{M-I} = 260$ K. A sharp reduction of the magnetic susceptibility below $T_{M-I}$ suggests the...
Temperature-induced barium de-trapping from a double-well potential in Ba6Ge25 (2003)
Schmidt, M., Radaelli, P. G., Gutmann, M. J., Billinge, S. J. L., Hur, N., Cheong, S. W.
The crystal structure of barium-germanium clathrate Ba6Ge25 was studied using neutron powder diffraction in the temperature range 20-300K. The compound was found to be cubic (S.G. P4_1 23) in the...
Ishibashi, H., Koo, T. Y., Hor, Y. S., Borissov, A., Horibe, Y., Radaelli, P. G., ...
At low temperatures, spinel CuIr$_2$S$_4$ is a charge-ordered spin-dimerized insulator with triclinic lattice symmetry. We find that x-rays induce a structural transition in which the local triclinic...
Blake, G. R., Chapon, L., Radaelli, P. G., Argyriou, D. N., Gutmann, M. J., Mitchell, J. F.
The phase diagram of Pr0.65(CaySr1-y)0.35MnO3, 0.6
Jorgensen, J. D., Hinks, D. G., Radaelli, P. G., David, W. I. F., Ibberson, R. M.
An anisotropic lattice anomaly near the superconducting transition temperature, Tc, was observed in MgB2 by high-resolution neutron powder diffraction. The a-axis thermal expansion becomes negative...
Peterson, P. F., Proffen, Th., Billinge, S. J. L., Kanatzidis, M. G., ...
High real-space resolution atomic pair distribution functions (PDFs) have been obtained from ZnSe(1-x)Te(x) using neutron powder diffraction. Distinct Zn-Se and Zn-Te nearest neighbor (nn) bonds,...
Mesoscopic and Microscopic Phase Segregation in Manganese Perovskites (2000)
Radaelli, P. G., Ibberson, R. M., Argyriou, D. N., Casalta, H., Andersen, K. H., ...
Mesoscopic (500-2000 Angstrom) and microscopic (5-20 Angstrom) phase segregation with temperature and magnetic field was studied in the model manganite Pr0.7Ca0.3MnO3 by high-resolution neutron...
Structure of HgBa2CuO4+delta (0.06 (1999)
Balagurov, AM, Sheptyakov, DV, Aksenov, VL, Antipov, EV, Putlin, SN, Radaelli, P G, ...
Radaelli, P. G., Cox, D. E., Capogna, L., Cheong, S-W., Marezio, M.
The crystallographic (charge-ordered) and magnetic superstructures of La0.333Ca0.667MnO3 were studied by high-resolution synchrotron x-ray and neutron powder diffraction. In the antiferromagnetic...
The structure of Hg Ba-2 Cu O-4 +delta at ambient and high pressure at 0.06 (1998)
Balagurov, AM, Sheptyakov, DV, Aksenov, VL, Antipov, EV, Putilin, SN, Radaelli, P G, ...