Infrared absorption spectra of manganese oxides La1−x−yRyCaxMnO3−δ

Abstract

Articles you may be interested inHigh-temperature transport properties of Ca 0.98 RE 0.02 MnO 3 − δ ( RE = Sm , Gd, and Dy) Appl. Phys. Lett. 98, 214101 (2011);High room temperature ferromagnetic moment of Ho substituted nanocrystalline BiFeO 3Infrared transmission spectra were measured systematically in polycrystalline La 1Ϫx Ca x MnO 3Ϫ␦ and several systems substituted by other rare earth ͑RE͒ ions such as Sm 3ϩ , Gd 3ϩ , Dy 3ϩ , etc., at La 3ϩ sites or Fe ions at Mn sites but keeping the nominal Mn 4ϩ /Mn 3ϩ Ϸ3/7. Two strong absorption peaks located around 600 and 350 cm Ϫ1 , which are associated with internal phonon modes, i.e., stretching and bending modes of MnO 6 octahedra, have been observed. Both of them are influenced by the concentrations of Ca and other RE ions substituting at the La and Mn sites. The details of the absorption peaks will be discussed on the basis of changes of the bond length of Mn-O and bond angle of Mn-O-Mn in MnO 6 octahedra.

Polaron transport in the paramagnetic phase of electron-doped manganites

“…Taking Θ ∼ 700 K as an average LO phonon energy, 18 and m * = m 0 implies α ∼ 2.6. The donor binding energy and …”

An Infrared Spectroscopic Study of the Insulator–Metal Transition and Charge-Ordering in Rare Earth Manganates, Ln1−xAxMnO3 (Ln=Rare Earth, A=Ca, Sr, Pb)

“…We report the results of a detailed infrared spectroscopic study on several manganates in this paper. The studies reported in the literature hitherto have by and large been concerned with frequency shifts in the re#ectivity and absorption spectra of a few limited compositions of manganates of the type¸n A MnO (11,12). The present investigation includes not only a variable-temperature and composition study of the manganates of the typȩ n A MnO , but also variable temperature studies of several charge-ordered manganates of the compositioņ n A MnO .…”

Crystal structure and thermal expansion of PrGaO3 in the temperature range 12–1253 K

“…In particular, NdGaO 3 , LaGaO 3 , PrGaO 3 as well as respective solid solutions are used as substrate materials for epitaxial growth of hightemperature superconductors (HTSC), collosal magnetoresistive films and for GaN film deposition [1][2][3][4][5][6]. A small lattice mismatch, similar coefficients of thermal expansion, high thermal and chemical stability, and in particular only small misfits at epitaxial growth temperatures are all-important features in growing layers of HTSC materials.…”