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Iron Oxide
Crystal:
FeOStructure: NaCl
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FeO and Fe2O3 are insulators; Fe3O4 can be semiconducting
Cohesive energy: |
eV |
Lattice parameter: |
2.14 Å |
Density: |
5.18 g/cm3 |
Stiffness constants: in 1011 dynes/cm2, at room temperature
c11: 35.9 (neutron data; Ref.1)
c12: 15.6
c44: 5.63
Compressibility (in 1011 dynes/cm2): 0.0447 ??
Poisson ratio:
Debye temperature: K
Melting temperature: 1420 ° C
Neel temperature: 198 K
Phonon spectrum discussed by:
Transverse optic phonon T0 (k=0): 333.7 cm-1 (Ref.2), n: 320, IR: 290
Longitude optic phonon L0 (k=0): 493.7 cm-1 , n: 526, IR 535
Gruneissen constant:
Ratio e*/e:
Photoelastic constants:
p11:
p12:
p44:
Band gap:
direct: eV.
indirect: eV.
Gap: eV.
First exciton: eV.
Photoemission for FeO, CoO, NiO:
Deduce values of Delta.
FeO
CoO -1.8 eV Co3+ low spin
NiO -1.7 eV Ni3+ low spin
Ref:
G. Grenet et al., On the interpretation of 3d
N ion photoemission spectra. I: A comparative study of the valence band of FeO, CoO, and NiO, J Chem. Phys. 74, 2163 (1981)
Band structure discussed: Phys. Rev. B16, 900 (1977)
Static dielectric constant: 12.7-14.2 or 24 (Ref.2) or 32.8 (Ref.1)
Optic dielectric constant: or 11.1 or 9.63
m
= 2.0 (Winchell & Winchell)e
(¥ )= 4.0
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:
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References:
1. G. Kugel, C. Carabatos, B. Hennion, B. Prevot, Lattice dynamics of Wustite (FeO), Phys. Rev. B16, 378 (1977)
2. R.V. Pisarev, V.V. Druzhinin, N.N. Nesterova, Optical absorption of ferroelectrical iron boracites, Phys. Stat. Sol. 40, 503 (1977)
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