Experimental and Theoretical Evidence of Weak Spin–Lattice Coupling in the Double Perovskite Sr2YRuO6

ABSTRACT Sr 2 YRuO 6 is a material that provides an ideal platform for studying magnetic frustration in three‐dimensional geometries. Herein, we combine Raman spectroscopy and density functional theory calculations to establish connections between the lattice dynamics and magnetic states in Sr 2 YRuO 6 single crystals. The x‐ray diffraction profiles reveal that Sr 2 YRuO 6 possesses an ordered double‐perovskite structure with distorted monoclinic symmetry. Three magnetic phase transitions are observed and linked to the presence of weak ferromagnetism at 135 K and short‐ and long‐range antiferromagnetic orderings at 32 and 26 K. The oxygen‐octahedron antistretching and stretching modes, observed at 570 and 766 cm −1 , exhibit anomalies near the magnetic phase transition temperatures, indicating an intriguing interplay between the lattice and spin degrees of freedom. Their spin–phonon coupling constants of 0.7 cm −1 reflect the weak spin–lattice interactions in Sr 2 YRuO 6 .