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Silver Iodide
Crystal: AgI
Structure: Various, here Wurtzite
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Lattice formation energy: |
-8.25 eV. (theory, Mayer and al.) (Ref.1) |
-8.65 eV. (experimental) (Ref.1) |
|
Lattice parameter: |
Å |
Density: |
g/cm3 |
Stiffness constants
: in 1011 dynes/cm2, at room temperature
c11: 2.93 (Ref.2)
c12: 2.13
c44: 0.373
Compressibility (in 1011 dynes/cm2): 0.417 ??
Poisson ratio:
Debye temperature: K
Melting temperature: K
Phonon spectrum discussed by:
G. Burns, F.H. Dacol & M.W. Shafer, Results from Raman spectra of the superionic conductor AgI, Phys. Rev. B16, 1417 (1977)
Also: See Ref.3, 4, 5, 6
Transverse optic phonon T0 (k=0): cm-1
Longitude optic phonon L0 (k=0): cm-1
Gruneissen constant:
Ratio e*/e:
Photoelastic constants:
p11:
p12:
p44:
Band gap:
direct: ~2 eV. (?) at K
indirect: eV. at ° K
Plasmon energy: eV.
Exciton energy: eV.
Photoemission:
Silver-halide valence & conduction states: temperature-dependence ultraviolet emission studies, R.S. Bauer & W.E. Spicer, Phys.Rev. B14, 4539 (1976)
See also:
D.E. Eastman, W.D. Grobman, J.L. Feeouf & M. Erbudak, Photoemission spectroscopy using synchrotron radiation. I: Overviews of valence-band structure for Ge, GaAs, GaP, InSb, ZnSe, CdTe & AgI, Phys. Rev. B9, 3473 (1974)
Band structure discussed by:
Static dielectric constant:
Optic dielectric constant:
Electron mobility:
Hole mobility:
Polaron coupling constant:
Effective mass:
conduction band:
valence band:
Electron affinity: ( in eV., from bottom of conduction band under vacuum)
Spin-orbit coupling: ( valence band)
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Other information:
Sigma: ~1.3-2.6/Ohm.cm.
Diffusion D: ~2.10exp(-5) cm2/sec. at 250 ° C
Beta AgI is hexagonal
Ref.: K. Funke, J. Kalus, R. E. Lechner, Quasielastic and inelastic scattering of cold neutrons from Silver Iodide, Sol. State Com. 14, 1021 (1974)
R.C. Hanson, T.A. Fjeldly & H.D. Hochheimer, Raman scattering from five phases of Silver Iodide, Phys. Stat. Solidi 70, 567 (1975)
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References:
1. C. Kittel, "Introduction to Solid State Physics", 2nd. Edition, New York: Wiley (1956)
2. T.A. Fjeldly, Elastic & piezoelectric constants of Silver Iodide: Study of a material at the covalent-ionic phase transition, Phys. Rev. B10, 3569 (1974)
3. G. Burns, F. H. Dacol, M. W. Shafer, Raman measurements of the superionic conductor AgI
4. M.J. Delanay and S. Ushioda, Raman spectra of silver-halide melts and sublattice melting in the superionic conductor Alpha-AgI, Phys. Rev B16, 1410 (1977)
5. R. Alben & G. Burns, Lattice dynamics of the superionic conductor AgI, Phys. Rev. B16, 3746 (1977)
6. W. Buhrer, R.M. Nicklow & Bruesch, Lattice dynamics of beta-(Silver Iodide) by neutron scattering,, Phys. Rev. B17, 3362 (1978)
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