First-order magneto-structural transition in single crystals of the honeycomb lattice Ruthenate Li${}_2$RuO${}_3$

Abstract

Li${}_2$RuO${}_3$ is known to crystallize in either $C2/m$ or $P{2}_1/m$ structures at room temperature. We report the first single crystal growth of Li${}_2$RuO${}_3$ and Na substituted crystals (Li${}_{0.95}$Na${}_{0.05}$)${}_2$RuO${}_3$ crystallizing in the $P{2}_1/m$ structure where a magneto-structural transition is observed at high temperatures. Using high temperature ($T\le 1000$~K) magnetic susceptibility $\chi$ measurements we study the magnetic anisotropy across the magneto-structural transition. Our results show for the first time that for Li${}_2$RuO${}_3$ the magnetic and structural transitions most likely occur at slightly different temperatures. The structural transition which is first order-like occurs first ($T\approx 570$~K) and drives the magnetic transition ($T\approx 540$~K). Rather surprisingly, just $5\%$ Na substitution for Li affects the magneto-structural transition in an interesting way. The first order transition temperature stays $\approx 540$~K, the magnetic anisotropy is reversed, and the Ru-Ru dimerization pattern changes from two short and four long Ru-Ru bonds per honeycomb in an armchair pattern for Li${}_2$RuO${}_3$ to four short and two long bonds per honeycomb in (Li${}_{0.95}$Na${}_{0.05}$)${}_2$RuO${}_3$ which can be viewed as two inter-penetrating armchair patterns.

An error in Fig2 has been corrected and some sentences have been added to the text to reflect this change

References in corpus (8)

• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• Scattering Continuum and Possible Fractionalized Excitations in $\alpha$-RuCl${}_3$
• Quantum spin Hall effect in a transition metal oxide Na2IrO3
• Single crystal growth from separated educts and its application to lithium transition-metal oxides
• Lattice-Tuned Magnetism of Ru4+(4d4) Ions in Single-Crystals of the Layered Honeycomb Ruthenates: Li2RuO3 and Na2RuO3
• Classical dimers and dimerized superstructure in orbitally degenerate honeycomb antiferromagnet
• Robust singlet dimers with fragile ordering in two-dimensional honeycomb lattice of Li${}_2$RuO${}_3$
• Effect of disorder on the dimer transition of the honeycomb-lattice compound Li${}_2$RuO${}_3$

Cited by in corpus (7)

• High-temperature magnetostructural transition in van der Waals-layered a-MoCl3
• Pressure-induced formation of rhodium zigzag chains in the honeycomb rhodate Li${}_2$RhO${}_3$
• Magnetic and electrical anisotropy with correlation and orbital effects in dimerized honeycomb ruthenate Li${}_2$RuO${}_3$
• Multipeak quasielastic light scattering and high-frequency electronic excitations in honeycomb Li${}_2$RuO${}_3$
• Revelation of Mott insulating state in layered honeycomb lattice Li${}_2$RuO${}_3$
• Doping effects on the valence bond solid of Li${}_2$RuO${}_3$ with Mn substitution
• Effect of Ti-doping on the dimer transition in Lithium Ruthenate