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Thorium Dioxide
Crystal: ThO2
Structure: fluorite
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Cohesive energy: |
eV |
Lattice parameter: |
Å |
Density: |
g/cm3 |
Stiffness constants: in 1011 dynes/cm2, at room temperature
c11: 36.7 (Ref.1) or 29.2 (Ref.2)
c12: 10.6 or 14.3
c44: 7.97 or 7.45
Compressibility (in 1011 dynes/cm2):
Poisson ratio:
Debye temperature: 393 K (but better
Melting temperature: 3300 ° C
Neel temperature: K
Phonon spectrum discussed by:
Transverse optic phonon T0 (k=0): 279 cm-1 for long IR, or 350±5 cm-1 at 77K. (LST relation) (Ref.3)
Longitude optic phonon L0 (k=0): 567 cm-1 or 465 cm-1, or also 464±1 cm-1 at 300K. (Raman) (Ref.3)
Gruneissen constant:
Ratio e*/e:
Photoelastic constants:
p11:
p12:
p44:
Band gap:
direct: 5.8 eV. (Ref.4) (see also Ref.5)
indirect: eV.
Gap: eV.
First exciton: eV.
Band structure discussed by:
Static dielectric constant: 18.9±0.4 (3*105 Hz. at room temperature) (Ref.6)
Optic dielectric constant:4.63 (Ref.4)
Thoria work: 2.5±0.5 eV.
O. Bastiansen, O. Hassel, A. Langseth, Dielectric properties of single crystals of BaTi; Nature 160, 129 (1947)
Electron mobility:
Hole mobility:
Polaron coupling constant:
Effective mass:
conduction band:
valence band:
Electron affinity: (in eV., from bottom of conduction band under vacuum)
Spin-orbit coupling: (valence band)
Cation polarisation: Å-3
Anion polarisation: Å-3
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References:
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