Temperature Dependence of the Raman Spectrum of BaTi<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">O</mml:mi></mml:mrow><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>

Perry, C. H.; Hall, Dylan

doi:10.1103/physrevlett.15.700

Cited by 312 publications

(178 citation statements)

References 10 publications

Supporting

Mentioning

146

Contrasting

Unclassified

Order By: Relevance

“…The orthorhombic-tetragonal-cubic sequence of transitions is supported by (1) the X-ray data of Liu and Liebermann (1993) which indicate a transition to a tetragonal form at around 1600 K; (2) the observation of the density and morphology of twins by transmission electron microscopy on samples quenched from 1673 K suggesting that above 1600 K CaTiO 3 is cubic (Wang and Liebermann 1993). The present Raman data can also be interpreted in the framework of such a transition sequence above 1500 K. The disappearance of all the first order bands as well as changes in second-order Raman scattering can be related to changes from orthorhombic (or tetragonal) to cubic symmetry with no allowed Raman modes as observed in other perovskite compounds like SrTiO3 (Perry et al 1967;Nilsen and Skinner 1968). This perovskite is cubic at room temperature and undergoes a displacive phase transition from cubic to tetragonal at 110 K. The evolution of the Raman spectra from 4 to 300 K is quite similar to that we have observed in CaTiO3.…”

Section: Symmetry Changesmentioning

confidence: 56%

Phase changes and thermodynamic properties of CaTiO3. Spectroscopic data, vibrational modelling and some insights on the properties of MgSiO3 perovskite

et al. 1993

View full text Add to dashboard Cite

Abstract. The effect of pressure (up to 21 GPa at room temperature) and temperature (up to 1570K at room pressure) on the Raman spectrum of CaTiO3 is presented. No significant changes, which could be attributed to a major structural change, are observed in the spectra up to 22 GPa. The pressure shifts of the Raman modes can be related to a significant compression of the Ti-O bond. Discontinuous changes in the spectra upon heating may be related to phase changes observed by calorimetry and X-ray diffraction. The important temperature shifts of some low-frequency modes can be related to an increase in the Ti-O-Ti angle in agreement with the X-ray data showing a decrease of the structural distortion with increasing temperature. These data are compared to those available for MgSiO3-perovskite and show that CaTiO3 is a good structural analogue for MgSiO3-perovskite. The present spectroscopic data are used to calculate the specific heat and entropy of CaTiO3. The role of the low frequency modes in the calculations is emphasized. Good agreement is observed between calculated and experimentally determined values in the 0-1300 K temperature range. A similarly defined model is proposed for MgSiO3-perovskite. It is found that the entropy lies between 57 and 64 J/mol/K at 298 K and between 190 and 200 J/mol/K at 1000 K in agreement with the values inferred from experimental equilibrium data. Finally we briefly discuss the values of the Griineisen parameters of both perovskites inferred from macroscopic and microscopic data.

show abstract

Section: Symmetry Changesmentioning

confidence: 56%

Phase changes and thermodynamic properties of CaTiO3. Spectroscopic data, vibrational modelling and some insights on the properties of MgSiO3 perovskite

et al. 1993

View full text Add to dashboard Cite

show abstract

“…Observed bands around 720, 515, 305, 260, and 180 cm ±1 are assigned to tetragonal BaTiO 3 . [22,23] The disappearance of the 305 cm ±1 band and the broadening of the 720 cm ±1 band, both characteristic of the tetragonal phase, at temperatures of 130±140 C, the Curie temperature of BaTiO 3 , depicts the transformation from the tetragonal to cubic phase. Two broad asymmetric bands near 230 and 535 cm ±1 in the cubic phase, arise from disorder in the cubic structure.…”

Section: Variable Temperature Micro-raman Spectroscopy Of Batio 3 Invmentioning

confidence: 99%

Barium Titanate Inverted Opals—Synthesis, Characterization, and Optical Properties

et al. 2002

View full text Add to dashboard Cite

“…Its frequency remains T -independent at ω T O3 ≈ 310 cm −1 in good agreement with the Raman data. 45,46 Except for the TO1 mode, doping with charge carriers does not have a significant effect on the TO phonon frequencies in BaTiO 3−δ ( Figure 5). Colossal decrease by ca.…”

Section: Optical Conductivitymentioning

confidence: 99%

Doping and temperature-dependent optical properties of oxygen-reducedBaTiO3−δ

et al. 2010

View full text Add to dashboard Cite

We report on optical properties of reduced BaTiO 3−δ at different doping levels including insulating and metallic samples. In all the samples, including metallic one, we observe structural phase transitions from the changes of the infrared active phonon modes. Metallic ground state is confirmed by the Drude-type low-frequency optical reflectance. Similar to SrTiO 3−δ we find that the mid-infrared absorption band in BaTiO 3−δ appears and grows with an increase in the oxygen vacancy concentration. Upon decrease in temperature from 300 K, the mid-infrared band shifts slightly to higher frequency and evolves into two bands: the existing band and a new and smaller band at lower frequency. The appearance of the new and smaller band seems to be correlated with the structural phase transitions.

show abstract

Temperature Dependence of the Raman Spectrum of BaTiO3

Abstract: The Raman spectrum of single-crystal BaTiO, has been observed in the Stokes region over the temperature range 4-475'K and becomes more complex as the temperature is lowered from the paraelectric state to the ferroelectric state, in which the crystal undergoes further first-

Cited by 312 publications

References 10 publications

Phase changes and thermodynamic properties of CaTiO3. Spectroscopic data, vibrational modelling and some insights on the properties of MgSiO3 perovskite

Phase changes and thermodynamic properties of CaTiO3. Spectroscopic data, vibrational modelling and some insights on the properties of MgSiO3 perovskite

Barium Titanate Inverted Opals—Synthesis, Characterization, and Optical Properties

Doping and temperature-dependent optical properties of oxygen-reducedBaTiO3−δ

Contact Info

Product

Resources

About