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Potassium Bromide
Crystal:
KBrStructure: NaCl
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Lattice formation energy: |
-6.87 eV. |
Lattice parameter: |
3.30 Å (3.262 at 0K.) |
Density: |
2.75 g/cm3 |
Stiffness constants
c11: 3.46 or 4.17
c12: 0.58 or 0.52
c44: 0.505 or 0.52
Compressibility (in 1011 dynes/cm2): 0.649 ??
Poisson ratio:
Debye temperature: 172 K
Melting temperature: K
Phonon spectrum discussed by:
A.D.B Woods, W. Cochran & B.N. Brockhouse, Lattice dynamics of alkali halide crystals, Phys.Rev. 119, 980 (1960)
Also: A.D.B.Woods,B.N. Brockhouse & R.A. Cowley Lattice dynamics of alkali halide crystals.II: Studies of KBr & NaI, Phys. Rev. 131, 1025 (1963)
Transverse optic phonon T0 (k=0): 101 or 123 cm-1
Longitude optic phonon L0 (k=0): 166 cm-1 (Hodby)
Gruneissen constant:
Ratio e*/e: 0.76
Photoelastic constants:
p11:
p12:
p44:
Band gap: direct: eV. at K
indirect: eV. at ° K
Plasmon energy: 13.3 eV. (Ref.1)
Exciton energy: 7.6 eV. (Ref.1) or 6.71 (Ref.2)
Band structure discussed by:
Static dielectric constant: 4.78 or 4.52 (Hodby)
Optic dielectric constant: 2.33 or 2.39 (Hodby)
Also for more information: Newton scattering investigation of the acoustic-mode Gruneinsen parameters in RbBr, G. Ernst, G. Krexner & G. Quittner, Phys.Rev. B29, 5805 (1984)
Electron mobility:
Hole mobility:
Polaron coupling constant:
a
= 3.52 ( for m*=1 )a
= 3.07 or 3.15 (Hodby)
Effective mass:
conduction band: |
0.428 (band mass) |
|
0.367 or 0.388 (Hodby) |
polaron: |
0.700 (Hodby) |
valence band: |
|
Electron affinity: ( in eV., from bottom of conduction band under vacuum)
0.6 eV.(Ref.3) also: 0.9 eV. (Ref.4)
Mott-Gurney estimate 3.52 eV. (Ref.5)
Jap.in estimates 0.36 eV. from colloids
Spin-orbit coupling:
0.49 ( valence band) (Ref.6)
( for all bromides, see Ref.7)
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Other information:
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References:
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