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Sodium Fluoride
Crystal:
NaFStructure: NaCl
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Lattice formation energy: |
-9.30 eV |
Lattice parameter: |
2.31 Å (2.295 at 0K.) |
Density: |
2.851 g/cm3 at 4K |
.
Stiffness constants: in 1011 dynes/cm2, at room temperature
c11: 9.630, 10.85 at 4K. (Ref.1) or 10.785 (Ref.2)
c12: 2.459, 2.270 at 4K. or 2.287
c44: 2.794, 2.889 at 4K. or 2.871
See also Other Information
Compressibility (in 1011 dynes/cm2): 0.206 ??
Poisson ratio:
Debye temperature: 491 K
Melting temperature: K
Phonon spectrum discussed by:
W.J.L. Buyers, Lattice dynamics of Sodium Fluoride Phys. Rev. 153, 923 (1967)
Transverse optic phonon T0 (k=0): 239 or 262 cm-1
Longitude optic phonon L0 (k=0): cm-1
Gruneissen constant:
Ratio e*/e: 0.93
Photoelastic constants:
p11:
p12:
p44:
Band gap:
direct: eV. at K
indirect: eV. at ° K
Plasmon energy: 20.7 eV. (Ref.3)
Exciton energy: 11.2 eV. (Ref.3) or 10.66 (Ref.4)
Valence band width: 4.9 eV.
Band structure discussed by: Kunz, see his work between 1967 & 1968
Static dielectric constant: 6.0 or 4.73
Optic dielectric constant: 1.74 or 1.75
Electron mobility:
Hole mobility:
Polaron coupling constant:
Effective mass: conduction band:
valence band:
Electron affinity: ( in eV., from bottom of conduction band under vacuum)
4.19, by Mott-Gurney, probably 3eV. too high (Ref.5)
Spin-orbit coupling: ( valence band)
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Other information:
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References:
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