A high-pressure Raman study of KReO4, RbReO4 and CsReO4 to 25 GPa and pressure-induced phase transitions

Jayaraman, A.; Kourouklis, G. A.; Uitert, L. G. Van; Grodkiewicz, W. H.; Maines, R. G.

doi:10.1016/0378-4371(89)90126-x

Cited by 33 publications

(17 citation statements)

References 12 publications

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“…According to Group Theory, the wolframite structure presents at the Γ point 18 Raman active modes (8A g + 10B g ) and 18 infrared ones (8A u + 10B u ). In this kind of compounds [8,26] Raman modes being their frequencies (ω) in good agreement with our calculations (see Table I). …”

Section: Raman Measurementssupporting

confidence: 77%

High-pressure phase transitions and compressibility of wolframite-type tungstates

Ruiz‐Fuertes

López-Moreno

Errandonea

et al. 2010

Journal of Applied Physics

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This paper reports an investigation on the phase diagram and compressibility of wolframite-type tungstates by means of x-ray powder diffraction and absorption in a diamondanvil cell and ab initio calculations. The diffraction experiments show that monoclinic wolframite-type MgWO 4 suffers at least two phase transitions, the first one being to a triclinic polymorph with a structure similar to that of CuWO 4 and FeMoO 4 -II. The onset of each transition is detected at 17.1 and 31 GPa. In ZnWO 4 the onset of the monoclinic-triclinic transition has been also found at 15.1 GPa. These findings are supported by density-functional theory calculations, which predict the occurrence of additional transitions upon further compression. Calculations have been also performed for wolframite-type MnWO 4 , which is 2 found to have an antiferromagnetic configuration. In addition, x-ray absorption and diffraction experiments as well as calculations reveal details of the local-atomic compression in the studied compounds. In particular, below the transition pressure the ZnO 6 and equivalent polyhedra tend to become more regular, whereas the WO 6 octahedra remain almost unchanged.

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Section: Raman Measurementssupporting

confidence: 77%

High-pressure phase transitions and compressibility of wolframite-type tungstates

Ruiz‐Fuertes

López-Moreno

Errandonea

et al. 2010

Journal of Applied Physics

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“…This has already been empirically found in scheelite compounds. The above hypothesis for the instability of the scheelite compounds with BX 4 /A radii ratios being near or below 1 is also supported by the transition pressures found in the alkaline-earth perrhenates and periodates families[56,58,59,147,148]. It has been shown that KReO 4 , RbReO 4 , KIO 4 and RbIO 4 crystallize in the scheelite structure.…”

mentioning

confidence: 62%

Pressure effects on the structural and electronic properties of ABX4 scintillating crystals

Errandonea

Manjón

2008

Progress in Materials Science

331

328

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Studies at high pressures and temperatures are helpful for understanding the physical properties of the solid state, including such classes of materials as, metals, semiconductors, superconductors, or minerals. In particular, the phase behaviour of ABX 4 scintillating materials is a challenging problem with many implications for other fields including technological applications and Earth and planetary sciences. A great progress has been done in the last years in the study of the pressure-effects on the structural and electronic properties of these compounds. In particular, the highpressure structural sequence followed by these compounds seems now to be better 2 understood thanks to recent experimental and theoretical studies. Here, we will review studies on the phase behaviour of different ABX 4 scintillating materials. In particular, we will focus on discussing the results obtained by different groups for the scheelitestructured orthotungstates, which have been extensively studied up to 50 GPa. We will also describe different experimental techniques for obtaining reliable data at simultaneously high pressure and high temperature. Drawbacks and advantages of the different techniques are discussed along with recent developments involving synchrotron x-ray diffraction, Raman scattering, and ab initio calculations.Differences and similarities of the phase behaviour of these materials will be discussed, on the light of the Fukunaga and Yamaoka´s and Bastide´s diagrams, aiming to improve the actual understanding of their high-pressure behaviour. Possible technological and geophysical implications of the reviewed results will be also commented.

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“…These studies suggest that TlReO 4 crystallizes in the pseudoscheelite structure at ambient conditions 18 and upon heating to 400 K and cooling to 200 K two phase transitions were observed 20,24 . Pressure-induced phase transitions have also been noticed at 0.5, 1.9 and 9.7 GPa 22,25 . Among them, the phase transition at 9.7 GPa triggers a color change of the material 22 .…”

Section: Introductionmentioning

confidence: 79%

Structural, vibrational, and electronic properties of TlReO4 studied using a first principles approach

Mondal¹,

Vaitheeswaran²,

Errandonea³

2019

Preprint

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The present work provides an extensive density functional theory study on the ambient phase of TlReO 4 . In this connection, a pseudo-potential approach has been considered for understanding the structural and vibrational properties of this material whereas the investigation of electronic band structure and associated optical properties of this material has been carried out through the implementation of full-potential linearized augmented plane wave (FP-LAPW) method. The calculated bulk modulus value 29.77 GPa using LDA functional is found to be close to experimental value 26 GPa. The order of elastic constant along the principal axis:indicates that the Re−O3 bonds play a crucial role in the structural and mechanical properties of this material. An analysis of the Born effective charge (BEC) along with Γ-point phonon frequencies through density functional perturbation approach (DFPT) have also shown the importance of the Re−O3 bond. The anisotropic nature of BEC is mainly found to be contributed due to the O3 atoms. An asymmetric stretching of the Re−O3 bond is found to be mainly responsible for high intense IR peak in the high-frequency range whereas the second most intense peak is due to the symmetric stretching of these bonds along with the asymmetric stretching of the Re−O2 bonds.In order to get the exact electronic band structure, spin orbit coupling (SOC) in addition to Tran-Blaha Modified Becke-Johnson (TB-mBJ) potential have been considered. Inclusion of SOC clearly shows a decreased band gap of 4.71 eV from TB-mBJ implemented band gap of 4.82 eV which is mainly attributed to a prominent splitting of Re d-states of about 0.08 eV. Study of density of states reveals that the conduction band bottom (CBB) is mainly made up of Re d-states but the main contribution to valence band top (VBT) is due to oxygen p-states. The bonding nature of this material has also been addressed using density of state (DOS) which is further verified through the electron charge density plot. Though the optical properties of this material are found to be anisotropic but optical isotropy can be seen in lower energy value specially in XX and YY directions which could be due to O2 and O3 type oxygen atoms.

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A high-pressure Raman study of KReO4, RbReO4 and CsReO4 to 25 GPa and pressure-induced phase transitions

Cited by 33 publications

References 12 publications

High-pressure phase transitions and compressibility of wolframite-type tungstates

High-pressure phase transitions and compressibility of wolframite-type tungstates

Pressure effects on the structural and electronic properties of ABX4 scintillating crystals

Structural, vibrational, and electronic properties of TlReO4 studied using a first principles approach

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