Structure and Magnetic Properties of a Family of Two-Leg Spin Ladder Compounds Ba 2 RE 2 Ge 4 O 13 (RE = Pr, Nd, and Gd–Ho)

作者：Jin Zhou, Andi Liu, Fangyuan Song, Langsheng Ling, Jingxin Li, Wei Tong, Zhengcai Xia, Gaoshang Gong, Yongqiang Wang, Jinkui Zhao, Hanjie Guo, Zhaoming Tian · 发表于：Inorganic Chemistry · 年份：2024 · DOI：10.1021/acs.inorgchem.4c03411 · 被引用次数：2 · 研究领域：Advanced Condensed Matter Physics、Magnetic and transport properties of perovskites and related materials、Crystal Structures and Properties

Compared with the intensive investigation on 3d transition metal (TM)-based spin ladder compounds, less attention has been paid to the ones constructed by rare earth (RE) ions. Herein, we report a family of RE-based spin ladder compounds Ba 2 RE 2 Ge 4 O 13 (RE = Pr, Nd, Gd–Ho) crystallized into a monoclinic structure with the space group C 2/ c . The RE ions are arranged on a two-leg spin ladder motif along the b -axis, where the rung and leg exchange interactions are bridged via RE–O–RE pathways and RE–O–Ge–O–RE routes, respectively. Moreover, the much shorter rung distance in RE 2 O 12 dimer units than the leg distance suggests that Ba 2 RE 2 Ge 4 O 13 compounds are strong-rung spin ladder systems. All of the synthesized Ba 2 RE 2 Ge 4 O 13 (RE = Pr, Nd, Gd–Ho) compounds exhibit dominant antiferromagnetic (AFM) interactions and the absence of magnetic order down to 1.8 K. Among the family members, Ba 2 Dy 2 Ge 4 O 13 can be described by J eff = 1/2 Kramers doublet states, and the low-temperature specific heat indicates the coexistence of the spin-dimerized state with a broad maximum at ∼2.4 K and long-range AFM order with T N = 0.81 K. This family of Ba 2 RE 2 Ge 4 O 13 compounds thereby provides a rare platform to investigate the novel spin ladder physics constructed by 4f electrons.