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Temperature Dependence of Infrared-Active Phonons in CaTiO3: A Combined Spectroscopic and First-Principles Study
Published
Author(s)
V Zelezny, J Petzelt, M F. Limonov, D Usvyat, A A. Volkov, Eric J. Cockayne
Abstract
Spectroscopic studies involving dielectric, submillimeter, infrared and Raman measurements were performed on a CaTiO3 single crystal, covering a broad spectral range (static to 10 THz) at temperatures from 6 to 300 K. The results show mode softening characteristic of an incipient ferroelectric with Tc -100 K. A signature of the soft mode is seen in the Raman spectra, even though the soft modes are not Raman-active to first order. First-principles calculations were used to identify the phonons responsible for the spectral features. Many of the major features are due to phonons in orthorhombic CaTiO3 that are associated with zone-boundary phonons of the cubic perovskite phase.
Citation
Physical Review B (Condensed Matter and Materials Physics)
Volume
66
Pub Type
Journals
Keywords
Ab initio phonon calculations, calcium titanate, infrared reflectivity, infrared spectroscopy, Kramer-Kronig analysis, raman spectroscopy, soft mode behavior
Zelezny, V.
, Petzelt, J.
, Limonov, M.
, Usvyat, D.
, Volkov, A.
and Cockayne, E.
(2002),
Temperature Dependence of Infrared-Active Phonons in CaTiO<sub>3</sub>: A Combined Spectroscopic and First-Principles Study, Physical Review B (Condensed Matter and Materials Physics)
(Accessed October 16, 2025)