Two-dimensional tetramer-cuprate Na5RbCu4(AsO4)4Cl2: phase transitions and AFMorder as seen by 87Rb NMR
Raivo Stern, Ivo Heinmaa, Annika Kriisa, Enno Joon, Sirje Vija,, Jeffrey Clayhold, Mutlu Kartin-Ulutagay, Xunhua Mo, Wendy Queen, and, Shiou-Jyh Hwu
TL;DR
This study uses 87Rb NMR to investigate the magnetic properties and phase transitions of a novel 2D cuprate with tetramer layers, revealing antiferromagnetic order and structural transitions.
Contribution
It provides the first NMR characterization of the magnetic order and phase transitions in a unique 2D tetramer-cuprate compound.
Findings
Antiferromagnetic order at TN = 15 K.
Identification of noncollinear spin arrangement.
Detection of structural phase transitions around 74 K and 110 K.
Abstract
We report the Rb nuclear magnetic resonance (NMR) results in a recently synthesized Na5RbCu4(AsO4)Cl2. This complex novel two-dimensional (2D) cuprate is an unique magnetic material, which contains layers of coupled Cu4O4 tetramers. In zero applied magnetic field, it orders antiferromagnetically via a second-order low-entropy phase transition at TN = 15(1) K. We characterise the ordered state by 87Rb NMR, and suggest for it a noncollinear rather than collinear arrangement of spins. We discuss the properties of Rb nuclear site and point out the new structural phase transition(s) around 74 K and 110 K.
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.