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Hafnium Dioxide

Crystal: HfO2 + 10% Y2O3

Structure: cubic

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Mechanical and structural properties:

Cohesive energy:	eV
Lattice parameter:	2.22 Å (nn distance)
Density:	g/cm³

Stiffness constants: in 10¹¹ dynes/cm², at room temperature

c₁₁: 38.2 (Ref.1)

c₁₂: 10.8

c₄₄: 6.0

Compressibility (in 10¹¹ dynes/cm²): 0.050 ??

Poisson ratio:

Debye temperature: K

Melting temperature: 2780 ° C

Neel temperature: K

Phonon spectrum discussed by:E. Anstassakis, B. Papanicolaon, T.M. Asher, Lattice dynamics and light scattering in Hafnia and Zirconia,, J. Phys. Chem. Sol. 36, 667 (1975)

Optic waves:

Transverse optic phonon T0 (k=0): cm^-1

Longitude optic phonon L0 (k=0): cm^-1

Gruneissen constant:

Ratio e*/e:

Elastic properties of Eu2O3-HfO2: microfiche IS-T-807

Also: S.L. Dole, O. Hunter, J.R. and F.W. Calderwood, Elastic properties of stabilised HfO2 compositions, J. Am. Ceram. Soc. 63, 136 (1980)

Elastic/lattice properties for monoclinic form:

S.L. Dole, O. Hunter, J.R. and C.J. Wooge, Elastic properties of monoclinic Hafnium oxide at room temperature, J. Am. Ceram. Soc. 60, 488 (1977)

Photoelastic constants:

p₁₁:

p₁₂:

p₄₄:

Electronic properties:

Band gap:

direct: 5.5 eV. (Ref.2)

indirect:15.7 eV. (plasmon?) (Ref.2)

Gap: eV.

First exciton: eV.

Band structure discussed by:

Static dielectric constant:

Optic dielectric constant: 4.93

Electron mobility:

Hole mobility:

Polaron coupling constant: a = (for m*=1 )

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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Other information:

Low thermal expansion and (Hf/Ti or Zr)O2: see S.R. Skaggs (1977)

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References:

V.I. Alexandrov et al., Molecular scattering of light in a single crystal of Hafnium Dioxide, Sov. Phys. Crystal. 18, 682 (1974)

J. Frandon, B. Brousseau, F. Pradal, Electronic excitations in some transition metals and their oxides. Characterisation energy loss measurements up to 50 eV., Phys.Stat.Sol. 98, 379 (1980)

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