_____________________________________________________________________
Germanium Dioxide
Crystal:
GeO2Structure: Rutile, also trigonal form
_____________________________________________________________________
Cohesive energy: |
eV |
Lattice parameter: |
Å |
Density: |
g/cm3 |
Stiffness constants: in 1011 dynes/cm2, at room temperature
c11: see Ref.1
c12:
c44:
Poisson ratio:
Compressibility (in 1011 dynes/cm2):
Debye temperature: K
Melting temperature: ° C
Neel temperature: K
Phonon spectrum discussed by:
M.E. Striefler, G.R. Barsch, Electronic, optic, and dielectric properties and their pressure derivatives of Rutile-structure oxides in a modified rigid ion approximation, Phys. Stat.S ol. 67, 143 (1975)
Transverse optic phonon T0 (k=0): cm-1 see Ref.2
Longitude optic phonon L0 (k=0): cm-1
Gruneissen constant:
Ratio e*/e:
Photoelastic constants:
p11:
p12:
p44:
See for information:
S.T. Pantelides, W.A. Harrison, Electronic structure, spectra, and properties of 4:2-SiO2 and GeO2, Phys. Rev. B13, 2667 (1976)
Band gap:
direct: eV.
indirect: eV.
Gap: eV.
First exciton: eV.
Static dielectric constant: //=12.2 and
Optic dielectric constant: //=4.4 and
^ =4.1
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
_____________________________________________________________________
References:
1. Wang, J. Geophys. Res. 78, 1262 (1973)
2. D.M. Roessler, W.A. Albers, IR reflectance of single crystal tetragonal GeO2, J. Phys. Chem. Soc. 33, 293 (1972)
3. See phonon spectrum
_____________________________________________________________________