Effect of high pressure on the crystal structure, magnetic, and vibrational properties of multiferroic RbFe(MoO sub(4)) sub(2)

• Published in: Physical review. B, Condensed matter and materials physics Condensed matter and materials physics, 2013-01, Vol.87 (1)
• Main Authors: Kozlenko, D P, Kichanov, S E, Lukin, E V, Dang, N T, Dubrovinsky, L S, Bykova, E A, Kamenev, K V, Hermann, H-P, Morgenroth, W, Shapiro, A Ya, Savenko, B N
• Format: Article
• Language: English
• Subjects: Condensed matter; Crystal structure; Diffraction; Magnetic permeability; Magnetic properties; Mathematical analysis; Phase transformations; Vectors (mathematics)
• ISSN: 1098-0121; 1550-235X

The structural, magnetic, and vibrational properties of RbFe(MoO sub(4)) sub(2) have been studied by means of x-ray and neutron powder diffraction, magnetic susceptibility measurements, and Raman spectroscopy at pressures up to 10 GPa. The gradual structural phase transition from the initial trigonal P3m1 phase to the monoclinic C2/c phase via the intermediate P3 phase was observed at P ~ 1 GPa. The triangular antiferromagnetic order with a propagation vector q = (1/3, 1/3, q sub(z)) in the suppressed trigonal phase remains incommensurate, and the q sub(z) value increases from 0.45 to 0.48 in the pressure range 0-2 GPa at T = 2 K. The pressure coefficient of the Neel temperature is equal to (1/T sub(N)) dT sub(N)/dP = 0.09 GPa super(-1). No evidence of the formation of the long-range magnetic order in the monoclinic phase was found. The pressure dependencies of the vibrational modes for the trigonal and monoclinic phases were obtained.