TY - JOUR
T1 - Quadrupole and hexadecapole ordering in DyB2C2
T2 - Direct observation with resonant x-ray diffraction
AU - Tanaka, Yoshikazu
AU - Inami, Toshiya
AU - Lovesey, Stephen W.
AU - Knight, Kevin S.
AU - Yakhou, Flora
AU - Mannix, Danny
AU - Kanazawa, Masayuki
AU - Ishida, Kohtaro
AU - Nanao, Susumu
AU - Nakamura, Tetsuya
AU - Yamauchi, Hiroki
AU - Onodera, Hideya
AU - Ohoyama, Kenji
AU - Nakamura, Yamaguchi
PY - 2004/1/29
Y1 - 2004/1/29
N2 - Direct evidence of the spatial ordering of Dy 4f quadrupole and hexadecapole moments in DyB2C2 is demonstrated by resonant x-ray diffraction enhanced by an electric quadrupole event (E2 resonance) at the Dy LIII absorption edge. The diffraction data show that the structural phase transition at TQ = 24.7K is accompanied by a reduction in the symmetry of the Dy site to 2/m, from 4/m, and the spatial ordering of the time-even Dy multipoles with Ag character. Below TQ the crystal structure is described by the space group P4 2/mnm and Dy ions occupy sites (4c). The distortion at TQ involves the lattice occupied by B and C ions, and it amounts to a buckling of B-C planes that are normal to the two-fold rotation axis of 2/m. An immediately plausible model of low-energy Dy states correlates data on the specific heat, our x-ray diffraction signals, and magnetic ordering below 15.3 K which has been observed in magnetic neutron diffraction.
AB - Direct evidence of the spatial ordering of Dy 4f quadrupole and hexadecapole moments in DyB2C2 is demonstrated by resonant x-ray diffraction enhanced by an electric quadrupole event (E2 resonance) at the Dy LIII absorption edge. The diffraction data show that the structural phase transition at TQ = 24.7K is accompanied by a reduction in the symmetry of the Dy site to 2/m, from 4/m, and the spatial ordering of the time-even Dy multipoles with Ag character. Below TQ the crystal structure is described by the space group P4 2/mnm and Dy ions occupy sites (4c). The distortion at TQ involves the lattice occupied by B and C ions, and it amounts to a buckling of B-C planes that are normal to the two-fold rotation axis of 2/m. An immediately plausible model of low-energy Dy states correlates data on the specific heat, our x-ray diffraction signals, and magnetic ordering below 15.3 K which has been observed in magnetic neutron diffraction.
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U2 - 10.1103/PhysRevB.69.024417
DO - 10.1103/PhysRevB.69.024417
M3 - Article
AN - SCOPUS:4143112663
VL - 69
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
SN - 0163-1829
IS - 2
ER -