Neutron diffraction study of 1D quantum spin system LiZrCuO with incommensurate magnetic structure

不整合磁気構造を有する一次元量子スピン系LiZrCuOの中性子構造解析

安井 幸夫*; 井川 直樹   ; 加倉井 和久

Yasui, Yukio*; Igawa, Naoki; Kakurai, Kazuhisa

CuOリボン鎖を持つ擬一次元量子スピン系LiZrCuOの磁気構造を中性子回折によって調べた。本物質は、およそ7Kにて反強磁性転移を示すが、この転移に伴って強誘電性が誘起されないという特徴を持つ。中性子粉末回折実験の結果、3KにてQ=(0, k, l0.488)および(h, 0, l0.488) (h, k and l=偶数)の超格子磁気反射が観測された。本報ではこれら中性子回折と磁性データから磁気構造を提案し、さらに本物質の反強磁性転移において強誘電性が誘起されない理由について議論する。

Magnetic structure has been studied by using neutron diffraction for quasi one-dimensional quantum spin system LiZrCuO with CuO ribbon chains. The CuO ribbon system LiZrCuO exhibits the antiferromagnetic transition at T 7 K, however, the magnetic transition is not accompanied with ferroelectricity. At 3K, we observed magnetic superlattice reflections at Q = (0, k, l) and (h, 0, l) (h, k and l = even) with 0.488 by the powder neutron diffraction. By the combined studies of neutron diffraction and magnetization data, the magnetic structure of LiZrCuO is proposed. On the bases of the obtained data, reasons for absence of ferroelectricity in LiZrCuO are discussed.