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Europium(II) titanate

Europium(II) titanate
Names
IUPAC name
Europium(II) titanate
Other names
Europium titante
Europium titanium oxide
Identifiers
3D model (JSmol)
ChemSpider
  • InChI=1S/Eu.3O.Ti/q+2;;;;-2
    Key: GJVYVJCMLXKLDJ-UHFFFAOYSA-N
  • O=[Ti-2](=O)(=O).[Eu+2]
Properties
EuTiO3
Molar mass 247.829g
Appearance Black Solid
Hazards
GHS labelling:
Warning
Related compounds
Other anions
 Europium(II) hydride
Europium(II) sulfate
Europium(II) sulfide
Related compounds
 Europium barium titanate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Europium(II) titanate is a black mixed oxide of europium and titanium, with the chemical formula of EuTiO3. It crystallizes in the perovskite structure.[1]

History

EuTiO3 was first examined in 1966 by McGuire, Shafer, Joenk, Halperin and Pickart where the magnetic structure was examined.[2] This compound received more attention at the beginning of the 21st century (2001 to 2015) due to the low-temperature phase transition to antiferromagnetic behavior at TN = 5.5 K, which has a significant influence on the dielectric constant.[3][4][5]

Preparation

Dried Eu2O3 and Ti2O3 are mixed 1:1 and reacted in an argon atmosphere at 1400 °C:[3]

The europium is reduced and the titanium is oxidized.

Properties

Europium(II) titanate has two different crystal forms depending on the temperature. The phase transition occurs at 282 K.[3][6] The low temperature form crystallizes in the tetragonal space group I4/mcm (space group No. 140) with the lattice parameters a = 551.92(2) pm, c = 781.64(8) pm (measured at 90 K). The higher temperature form has a cubic form with Pm3m (space group No. 221) with lattice parameter a = 390.82(2) pm (measured at 300 K).[3][7] The transition temperature of the crystal structure from the low-temperature to the high-temperature phase increases with increasing pressure.[8] The compound becomes G-type antiferromagnetic below 5.5 K.[9] The specific heat capacity is 125 J·mol−1·K−1 (at 600 K).[1] 125 J·mol−1·K−1290 K is 7,6 W·m−1·K−1 and the electrical conductivity is 105 (Ω·m)−1(at 330 K).[1]

References

  1. ^ a b c 1. Muta, Hiroaki (2005). "Thermoelectric Properties of Lanthanum-Doped Europium Titanate". Materials Transactions. 46 (7): 1466–1469. doi:10.2320/matertrans.46.1466.{{cite journal}}: CS1 maint: numeric names: authors list (link)
  2. ^ T. R. McGuire, M. W. Shafer, R. J. Joenk, H. A. Halperin, and S. J. Pickart (1966). "Magnetic structure of EuTiO3". Journal of Applied Physics. 37 (3): 981. Bibcode:1966JAP....37..981M. doi:10.1063/1.1708549.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  3. ^ a b c d J. Köhler, R. Dinnebier, A. Bussmann-Holder (2012). "Structural instability of EuTiO3 from X-ray powder diffraction". Phase Transitions. 85 (11): 949–955. arXiv:1205.5374. Bibcode:2012PhaTr..85..949K. doi:10.1080/01411594.2012.709634. S2CID 94709465.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  4. ^ S. Kamba, D. Nuzhnyy, P. Vaněk, M. Savinov, K. Knížek, Z. Shen, E. Šantavá, K. Maca, M. Sadowski, J. Petzelt (2007). "Magnetodielectric effect and optic soft mode behaviour in quantum paraelectric EuTiO3 ceramics". Europhysics Letters. 80 (2): 27002. arXiv:0706.1882. Bibcode:2007EL.....8027002K. doi:10.1209/0295-5075/80/27002. S2CID 13856279.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  5. ^ T. Katsufuji and H. Takagi (2001). "Coupling between magnetism and dielectric properties in quantum paraelectric EuTiO3". Physical Review B. 64 (5): 054415-1–054415-4. Bibcode:2001PhRvB..64e4415K. doi:10.1103/PhysRevB.64.054415.
  6. ^ Bussmann-Holder, J. Köhler, R. K. Kremer, J. M. Law (2011). "Relation between structural instabilities in EuTiO3 and SrTiO3". Physical Review B. 83 (21): 212102. arXiv:1105.6029. Bibcode:2011PhRvB..83u2102B. doi:10.1103/PhysRevB.83.212102. S2CID 118638434.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  7. ^ A. Bussmann-Holder, Z. Guguchia, J. Köhler, H. Keller, A. Shengelaya, A. R. Bishop (2012). "Hybrid paramagnon phonon modes at elevated temperatures in EuTiO3". New Journal of Physics. 14 (9): 093013. arXiv:1205.6287. Bibcode:2012NJPh...14i3013B. doi:10.1088/1367-2630/14/9/093013. S2CID 118479381.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  8. ^ P. Parisiades, E. Liarokapis, J. Köhler, A. Bussmann-Holder, M. Mezouar (2015). "Pressure-temperature phase diagram of multiferroic EuTiO3". Physical Review B. 92 (6): 064102. arXiv:1505.05049. Bibcode:2015PhRvB..92f4102P. doi:10.1103/PhysRevB.92.064102. S2CID 118250289.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  9. ^ Z. Guguchia, H. Keller, A. Bussmann-Holder, J. Köhler, R. K. Kremer (2013). "The low temperature magnetic phase diagram of EuxSr1−xTiO3". European Physical Journal B. 86 (10): 409–412. Bibcode:2013EPJB...86..409G. doi:10.1140/epjb/e2013-40632-y. S2CID 123512501.{{cite journal}}: CS1 maint: multiple names: authors list (link)
Quelle: https://en.wikipedia.org/wiki/Europium(II)_titanate