Structural phase transition accompanying with quadrupolar ordering in DyB4 with Shastry-Sutherland type geometrical frustration has been studied by X-ray diffraction. Previous study [D. Okuyama et al.: J. Phys. Soc. Jpn. 74 (2005) 2434.] using resonant X-ray scattering revealed short-range ordering of the Ozx-type quadrupolar moments and the c-plane component of the magnetic moments in addition to long-range ordering of the c-axis component of the magnetic moments. The present report focuses on the lattice distortion below the quadrupolar ordering temperature at TN2=12.7 K. The (0 0 l=integer) fundamental lattice reflection splits into four peaks along the h and k directions and the (h=even 0 0) reflection becomes broad along the l direction. This indicates that a structural transition from tetragonal to monoclinic takes place below TN2 together with the ordering of the quadrupolar moments.
@article{arxiv.0709.2274,
title = {Quadrupolar Order and Structural Phase Transition in DyB4 with Geometrical Frustration},
author = {Daisuke Okuyama and Takeshi Matsumura and Hironori Nakao and Youichi Murakami},
journal= {arXiv preprint arXiv:0709.2274},
year = {2007}
}
Comments
3 pages, 4 figures, the Proceedings of ASR-WYP-2005