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Cesium Bromide

Crystal: CsBr

Structure: CsCl

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Mechanical and structural properties:

Lattice formation energy:	-6.35 eV. (theory, Mayer and al.) (Ref.1)
	-6.45 eV. (experimental) (Ref.1)
Lattice parameter:	3.71 Å
Density:	g/cm³

Stiffness constants: in 10¹¹ dynes/cm², at room temperature

c₁₁: 3.10 (Ref.2) or 2.00

c₁₂: 0.84 or 0.78

c₄₄: 0.75 or 0.76

Compressibility (in 10¹¹ dynes/cm²): 0.627 ??

Poisson ratio:

Debye temperature: K

Melting temperature: K

Phonon spectrum discussed by:

J.F. Vetelino, Lattice dynamics, mode Gruneisen parameters & coefficient of thermal expansion of CsCl, CsBr & CsI, Phys. Rev. B2, 2167

Also: S. Rolandson & G. Raunio, Lattice dynamics of CsBr, Phys. Rev. B4, 4617 (1971)

Transverse optic phonon T0 (k=0): cm^-1

Longitude optic phonon L0 (k=0): cm^-1

Gruneissen constant:

Ratio e*/e: 0.78

Photoelastic constants:

p₁₁:

p₁₂:

p₄₄:

Electronic properties:

Band gap:

direct: eV. at K

indirect: eV. at ° K

Plasmon energy: eV.

Exciton energy: 6.83 eV. (Ref.3)

Band structure discussed by:

L. Nosenzo & E. Reguzzoni, Analysis of the electronic structure in Cesium halides by reflectance & thermoreflectance studies, Phys. Rev. B19, 2314 (1979)

E. Boursey and J.-Y. Rongin, Absorption spectra of Cesium halides at 20K. from 12 to 20 eV., Sol. State Com. 9, 1049 (1971)

Static dielectric constant: 6.51

Optic dielectric constant: 2.78

Electron mobility:

Hole mobility:

Polaron coupling constant: a = 4.1 ( 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)

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References:

C. Kittel, "Introduction to Solid State Physics", 2nd. Edition, New York: Wiley (1956)

Ted R. Musgrave, "Understanding problems for chemical principles", Philadelphia: Saunders (1978)

W.B. Fowler, "Physics of Color Centers", New York: Academic Press (1968)

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