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Germanium Dioxide

 

Crystal: GeO2

Structure: Rutile, also trigonal form

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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 ^ =14.5 (Ref.2 & 3)

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

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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

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