American Physical Society, Physical review B, 21(73)
DOI: 10.1103/physrevb.73.214301
Full text: Unavailable
The temperature-dependent Raman spectra of orthorhombic RMnO3 (R=Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Y) were studied in the 5–300 K temperature range. It was established that while the materials with large R3+ ionic radius rR and A-type antiferromagnetic order (R=Pr,Nd,Sm) exhibit significant phonon softening and other anomalies with decreasing temperature near and below TN, the effect of magnetic ordering is much weaker or negligible in compounds with R=Eu, Gd, Tb, Dy, Ho, and Y, characterized by small rR and incommensurate magnetic structure. The results are discussed accounting for the variations with rR of the type of magnetic ordering and related spin-phonon interaction.