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Title: Scaling spin–phonon and spin–spin interactions in magnetoelectric Gd{sub 1−x}Y{sub x}MnO{sub 3}

We present a systematic study of the structure and lattice dynamics at room temperature, and the phonon behavior at low temperatures in orthorhombic Gd{sub 1−x}Y{sub x}MnO{sub 3} manganites, with 0≤x≤0.4. Powder x-ray diffraction and Raman scattering at ambient conditions reveal that the Jahn–Teller distortion is composition-independent, while the Mn–O1–Mn bond angle increases by about 0.5° from x=0 to x=0.4. The spin–phonon coupling was ascertained from the relation between the renormalized wavenumber of the in-plane O2 stretching mode, associated with the spin–spin correlation function. The balance between competitive magnetic interactions is discussed based on the temperature dependence of the phonon frequency renormalization. - Graphical abstract: Wavenumber of the in-plane O2 stretching mode as a function of the spin–spin correlation function, for GdMnO{sub 3} (a), and Gd{sub 0.8}Y{sub 0.2}MnO{sub 3} (b). - Highlights: • Crucial role of structural distortions induced by ion substitution. • Tuning of magnetic interactions through ion substitution. • Facing spin–phonon coupling and competitive exchange magnetic interactions. • Scaling of spin–phonon and spin–spin mechanisms.
Authors:
 [1] ;  [2] ;  [1] ;  [2] ;  [3] ;  [3] ;  [4] ;  [1]
  1. IFIMUP and IN-Institute of Nanoscience and Nanotechnology, Departamento de Física e Astronomia da Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, 687, Porto 4169-007 (Portugal)
  2. Centro de Química—Vila Real, Departamento de Química, Universidade de Trás-os-Montes e Alto Douro, Vila Real 5000-801 (Portugal)
  3. Materials Research and Technology Department, Luxembourg Institute of Science and Technology, 41, Rue du Brill, Belvaux L-4422 (Luxembourg)
  4. (Luxembourg)
Publication Date:
OSTI Identifier:
22486722
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 228; Other Information: Copyright (c) 2015 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; BOND ANGLE; CORRELATION FUNCTIONS; CORRELATIONS; ELECTRICAL PROPERTIES; ELECTRON-PHONON COUPLING; GADOLINIUM COMPOUNDS; JAHN-TELLER EFFECT; MAGNETIC PROPERTIES; MANGANATES; ORTHORHOMBIC LATTICES; POWDERS; RAMAN SPECTROSCOPY; RENORMALIZATION; SPIN; TEMPERATURE DEPENDENCE; X-RAY DIFFRACTION; YTTRIUM COMPOUNDS