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Nickel Oxide

Crystal: NiO

Structure: ZB

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Mechanical and structural properties:

Cohesive energy:	eV
Lattice parameter:	2.08 Å
Density:	6.67 g/cm³

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

c₁₁:

c₁₂:

c₄₄:

Compressibility (in 10¹¹ dynes/cm²):

Poisson ratio:

Debye temperature: K

Melting temperature: 1990 ° C

Neel temperature: 523 K

Phonon spectrum discussed by:

R.A. Coy, C.W. Thompson, and E. Gurmen, Phonon dispersion in NiO, Sol. St. Comm. 18, 845 (1976)

Also: K.S. Upadhyaya and R.K. Singh, Shell model lattice dynamics of transition metal-oxides, J. Phys. Chem. Sol. 35, 1175 (1974)

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

Longitude optic phonon L0 (k=0): 17 THz or 0.070 eV.

Gruneissen constant:

Ratio e*/e:

Photoelastic constants:

p₁₁:

p₁₂:

p₄₄:

Electronic properties:

Band gap:

direct: 3.7 eV.

indirect: eV.

Gap: eV.

First exciton: eV.

Conductivity: Ea vs. T: magnetic effects:

A. Steinbrunn and C. Bourgeois, Confirmation of the spin dependent charge courrier transport in pure single crystals of NiO, J. Phys. Chem. Sol. 43, 651 (1982)

See also: Keem et al. M. B37, 537 (1978)

E(A): ~0.26 eV.

Band structure discussed by: L.F. Mattheis, Phys. Rev. B5 (1972)

NiO electrons structure-Experimental effects of correlation:

A.B. Kunz, Electronic structure of NiO, J. Phys. C14, L455 (1981)

XPS energy levels:

A.H. Monish, E. Clark, High-field Mossbauer study of manganese-zinc ferrites, Phys. Rev. B11, 277 (1975)

Static dielectric constant: 10.31 or 11.75 or 9.7-11.9

Optic dielectric constant: 5.70 or 6.1

m = 2.37, e (¥ )= 5.62 (Ref.1)

Electron mobility:

Hole mobility:

Polaron coupling constant: a = 1.26 ( 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)

Cation polarisation: Å^-3

Anion polarisation: Å^-3

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Other information:

Interatomic interactions in NiO, to include magnon data (superexchange IN): S. Gosh, A. N. Basu and S. Sengupta, Effective interatomic interactions and lattice mechanical properties of the NiO crystal for both paramagnetic and antiferromagnetic phases, Phys.Rev. B25, 5953 (1982)

Unrestricted Hartree-Fock for (NiO6)-10 giving overlapping non-interacting p, d states: G.T. Surrat, and A.B. Kunz, Unrestricted Hartree-Fock calculations for a cluster model of NiO, Sol.St.Com. 23, 555 (1977) (What about charge transfer?)

See below for supplementary information on NiO

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References:

1. N.H. Winchell and A.N. Winchell, "Elements of optical mineralogy: an introduction to microscopic petrography. Part 2: description of minerals, with special reference to their optical and microscopic characters", 2nd. Ed., New York: Wiley, 1927

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Supplementary information on NiO

Oxygen K near-edge fine structure: An electron-energy-loss investigation with comparisons to new theory for selected 3d transition-metal oxides.

L.A. Grunes and R.D. Leapman. Phys.Rev. B25, 7157 (1982)

Excitations of the oxygen 1s subshell in selected 3d transition-metal oxides have been studied by inelastic scattering of 75-keV electrons. Striking variations in the near-edge fine structure are reported and an interpretation is developed based on an empirical molecular orbital energy-level model. We compare our observed fine structure with that evinced in the metal K and L3 edges in these same oxides. While the molecular orbital model seems adequate for interpreting the spectra of TiO2, it fails for at least some of the oxides studied. For example, in oxygen 1s excitation spectrum gives results showing that the near-edge structure is not adequately described by the unoccupied density of states of the solid before core-hole excitation. Instead, the initial spectral peaks are shown to be core excitons. However, for TiO2, a tight-binding extended Huckel calculation neglecting the core hole yields a density of states that displays peaks in good agreement with the experimental data. Speculations on the origin of the difference between the spectra of NiO and TiO2 are offered.

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