Temperature Dependence of the Hyperfine Interaction at 181Ta in SrHfO3

López-García, A.; Presa, Patricia de la; Ayala, A. P.

doi:10.1006/jssc.2001.9112

Cited by 7 publications

(6 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Conversely to the A site substitution, the Bi site substitution by Te does not seem to affect the damping character of the soft mode, since our results show the same underdamped behaviour as that observed in undoped SBN [23]. The increment on the damping of the soft mode due to the A site substitution originates in the larger ionic radius of Ba when compared with Sr [24]. The Bi substitution should induce a similar effect, since these cations are also placed in the octahedral neighbour.…”

Section: Resultssupporting

confidence: 68%

“…These hyperfine parameters correspond to the orthorhombic structure. In the SrHfO 3 perovskite, which also has an orthorhombic lattice at room temperature, it was found that ω Q = 19.8 3 Mrad s −1 , η = 0.47 2 and δ = 24 2 % [24]. Comparing the respective values of ω Q (or the intensity of V Z Z ), an increment of a factor ∼6 is observed (see below).…”

Section: Resultsmentioning

confidence: 92%

See 1 more Smart Citation

The orthorhombic to tetragonal phase transition in Bi_1.75Te_0.25SrNb_1.75Hf_0.25O₉

Alonso

Ayala

Castro

et al. 2004

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

The necessity to produce materials with better performances than those observed in ferroelectric perovskites has generated the creation of new oxides, especially those belonging to the Aurivillius family. In the last few years much attention has been paid to the study of these materials, and this has opened up new fields due to their basic and applied properties. In this contribution a Raman analysis and a hyperfine study by perturbed angular correlations spectroscopy of Bi 1.75 Te 0.25 SrNb 1.75 Hf 0.25 O 9 were carried out to reveal information about the lattice and the electronic structure. By the use of these techniques, it was observed that the ferroelectric to paraelectric phase transition at about 570 K is driven by a soft mode, and the broadening of the dielectric constant as a function of temperature previously observed at T C is connected to disorder in the Bi/Te-O layer.

show abstract

Section: Resultssupporting

confidence: 68%

Section: Resultsmentioning

confidence: 92%

The orthorhombic to tetragonal phase transition in Bi_1.75Te_0.25SrNb_1.75Hf_0.25O₉

Alonso

Ayala

Castro

et al. 2004

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

show abstract

“…In this work, the phase transition at T C1 was classified as first order, and the other two as second order or continuous [5]. The hyperfine interaction that characterizes both oxides was also detected and has been determined to be different [6][7][8].…”

Section: Introductionmentioning

confidence: 91%

Electron bonds and hyperfine electric field gradient in the Sr_1−xBa_xHfO₃family

López-García¹,

Alonso²

2005

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

show abstract

“…Los valores correspondientes para el rutenato son: ω Q = 21.3 4 , η = 0.47 3 y δ = 13 4 % y para el hafnato ω Q = 19.0 4 , η = 0.48 3 y δ = 26 2 %. Si el gce fuera originado únicamente por los 6 oxígenos más próximos a la sonda, de acuerdo al modelo de cargas puntuales, aquel y la frecuencia cuadrupolar serían inversamente proporcionales al cubo de la distancia M-O.…”

Section: Dado Que El 181unclassified

Interacciones cuadripolares en SrZrO<sub>3</sub>

López-García¹,

Alonso²

2004

Bol. Soc. Esp. Ceram. Vidr.

View full text Add to dashboard Cite

Las perovskitas SrMO 3 con M = Ru, Zr ó Hf presentan características estructurales muy similares. Son ortorrómbicas a temperatura ambiente (TA) y transitan a estructuras tetragonal (I4/mcm) y cúbica (Pm3 -m) a más alta temperatura. Estas diferentes estructuras están caracterizadas por la rotación del octaedro de oxígenos según distintos ejes, como si fuera una estructura casi rígida. Conforme aumenta la temperatura, se observa que en las transiciones de fase cambian los ejes de rotación, mientras que las distancias M-O permanecen casi constantes (≤1%), en todo el rango de temperaturas medido. En la transición de la fase tetragonal a cúbica la rotación es alrededor del eje c y el ángulo de rotación tiende a cero mediante la forma φ(T) ∼ φ 0 (T C -T) β . β es el exponente crítico y se ajustaron valores muy próximos a ½, ¼ y 1 /8 para M = Hf, Zr y Ru, respectivamente. La estructura electrónica debería seguir los cambios observados en la estructura cristalina y puede ser estudiada mediante la interacción cuadripolar hiperfina usando la espectroscopía de Correlaciones Angulares Perturbadas (CAP). En esta contribución se analizan dichos resultados en SrZrO 3 .Palabras clave: perovskitas, transiciones de fase, interacciones hiperfinas, defectos. Quadrupole interactions in SrZrO 3 .The SrMO 3 compounds with M = Ru, Zr ó Hf display similar structures. They are orthorhombic at room temperature (RT) and transform into tetragonal (I4/mcm) and cubic (Pm3 -m) at higher temperatures. These structures are characterized by rotations of the quasi-rigid oxygen octahedron through different axes. As temperature increases the rotation axes changes at the transition temperature but the M-O distances remain almost constant (1%) in the whole temperature range. The crystallographic study of the tetragonal to cubic transformation shows that it occurs by the rotation φ(T C )→0 of the rigid oxygen octahedron about the c axis. This transition is of second order and can be described by. β is the critical exponent and was fitted to ½ , ¼ and 1 /8 for M = Hf, Zr and Ru, respectively. The electronic structure of these compounds should follows such changes and can be studied through the measurement of the quadrupole interaction as a function of temperature. In this contribution these results obtained by Perturbed Angular Correlations spectroscopy (PAC) for SrZrO 3 are discussed.Key words: perovskites, phase transitions, hyperfine interaction, defects INTRODUCCIÓNLos óxidos llamados perovskitas tienen una composición química de la forma AMO 3 . Bajo este nombre existe un número apreciable de compuestos y comprende elementos de la tabla periódica tal que la suma de las valencias de A más M sea 6. De acuerdo a su composición, estos óxidos tienen diferentes propiedades mecánicas, eléctricas, magnéticas, ópticas, de transporte, etc., que importa estudiar tanto desde el punto de vista básico como aplicado. Presentan estructuras cristalinas sencillas y la fase de más alta temperatura es cúbica. En esta fase, los cationes A ocupan los vértices del cuerpo...

show abstract

Temperature Dependence of the Hyperfine Interaction at 181Ta in SrHfO3

Cited by 7 publications

References 18 publications

The orthorhombic to tetragonal phase transition in Bi_1.75Te_0.25SrNb_1.75Hf_0.25O₉

The orthorhombic to tetragonal phase transition in Bi_1.75Te_0.25SrNb_1.75Hf_0.25O₉

Electron bonds and hyperfine electric field gradient in the Sr_1−xBa_xHfO₃family

Interacciones cuadripolares en SrZrO<sub>3</sub>

Contact Info

Product

Resources

About

Temperature Dependence of the Hyperfine Interaction at 181Ta in SrHfO3

Cited by 7 publications

References 18 publications

The orthorhombic to tetragonal phase transition in Bi1.75Te0.25SrNb1.75Hf0.25O9

The orthorhombic to tetragonal phase transition in Bi1.75Te0.25SrNb1.75Hf0.25O9

Electron bonds and hyperfine electric field gradient in the Sr1−xBaxHfO3family

Interacciones cuadripolares en SrZrO<sub>3</sub>

Contact Info

Product

Resources

About

The orthorhombic to tetragonal phase transition in Bi_1.75Te_0.25SrNb_1.75Hf_0.25O₉

The orthorhombic to tetragonal phase transition in Bi_1.75Te_0.25SrNb_1.75Hf_0.25O₉

Electron bonds and hyperfine electric field gradient in the Sr_1−xBa_xHfO₃family