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Potassium Chloride
Crystal:
KClStructure: NaCl
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Lattice formation energy: |
-7.19 eV. |
Lattice parameter: |
3.14 Å (3.116 at 0K.) |
Density: |
2.038 or 1.98 g/cm3 |
Stiffness constants: in 1011 dynes/cm2, at room temperature
c11: 3.98 or 4.832
c12: 0.62 or 0.54
c44: 0.625 or 0.663
Compressibility (in 1011 dynes/cm2): 0.574 ??
Poisson ratio: 0.2494 (Voigt)
Debye temperature: 235 K
Melting temperature: K
Phonon spectrum discussed by:
G. Raunio & S. Rolandson, Lattice dynamics of NaCl, KCl, RbCl & RbF, Phys.Rev. B2, 2098 (1970)
Transverse optic phonon T0 (k=0): 142 or 151 cm-1
Longitude optic phonon L0 (k=0): 212 cm-1 (Hodby) which means: 3.99*1013 rad/sec.
Gruneissen constant:
Ratio e*/e: 0.80
Photoelastic constants:
p11:
p12:
p44:
Band gap:
direct: 6.4 eV. at K
indirect: eV. at ° K
Plasmon energy: 14.2 eV. (Ref.1)
Exciton energy: 8.6 eV. or 7.79 eV. (Ref.2)
Conduction band width: 0.6 eV.
Electronic band structure of the alkali halides. II:Critical survey of theorical calculation, R.T. Poole, J. Liesegang, R.C.G. Leckey & J.G. Jenkin, Phys. Rev. B11, 5194 (1975)
which gives:
Valence band width: |
2.7 eV. |
Gap: |
8.4 eV. |
Electron affinity: |
0.5 eV. |
Band structure discussed by:
N.O. Lipari & A.B. Kunz, Energy bands for KCl, Phys.Rev. B4, 4639 (1971)
Summary of band theory:
Mixed approach of linear-combination-of-atomic-orbitals & orthogonalized-plane-wave methods to the band-structure calculation of alkali-halide crystals, S.M. Mujibur Rahman, A.M. Harun Ar Rashid & S.M. Chowdhury, Phys. Rev. B14, 2618 (1976)
Static dielectric constant: 4.68 or 4.49 (Hodby)
Optic dielectric constant: 2.13 or 2.20 (Hodby)
Other information for T, P dependence:
Pressure & temperature dependence of the static dielectric constants of KCl, LiF & MgO, R.A. Bartells & A. Smith, Phys.Rev. B7, 3885 (1973)
Electron mobility:
Hole mobility:
Polaron coupling constant:
a
= 5.8 ( for m*= -1 )a
= 3.97 for true m*or
a = 3.46 or 3.60 (Hodby)
Effective mass:
conduction band: 0.496 (band mass)
valence band: 0.432 or 0.467 (Hodby) 0.922 for a polaron
Electron affinity: ( in eV., from bottom of conduction band under vacuum)
0.6 (Ref.3 & 4)
Mott-Gurney estimate 3.78 (Ref.7)
Japin estimates 0.23 eV. from colloids
Spin-orbit coupling:
0.11 ( valence band) (Ref.5)
0.13 (excitons in chloride) (Ref.6)
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Other information:
S. Hart, J.of Phys. D10, Letter261 (1977)
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References:
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