Radiation damage studies by x-ray photoelectron spectroscopy. II. Electron irradiated Li/sub 2/CrO/sub 4/ and Li/sub 2/WO/sub 4/
Single crystals of Li/sub 2/CrO/sub 4/ and Li/sub 2/WO/sub 4/ were irradiated in situ with 0.3--1.6 keV electrons in an UHV x-ray photoelectron spectrometer. Chemical shifts of core-level peaks in XPS spectra indicate formation of Cr(III) on the irradiated Li/sub 2/CrO/sub 4/ surface and of W (IV) and W (V) on the irradiated Li/sub 2/WO/sub 4/ surface. Accompanying formation of the reduced species, new peaks attributable to photoelectrons from non-bonding orbitals appear at binding energies just below the respective Fermi levels. A lower limit of the G value for Cr(III) formation is estimated to be about 1.3 x 10/sup -2/ from the differential energy loss of the incident electrons. Comparison of this G value with previous data determined by ESR suggests that solid surfaces are far more sensitive to radiation damage than the bulk. The irradiation of Li/sub 2/WO/sub 4/ causes a shift in the entire XPS spectrum to lower binding energy, initially approx.2 eV, which decreases over a 20 h period until the original peak positions are recovered. This is interpreted in terms of surface charging caused by electron irradiation.
- Research Organization:
- Materials and Molecular Research Division, Lawrence Berkeley Laboratory
- OSTI ID:
- 6548629
- Journal Information:
- J. Chem. Phys.; (United States), Vol. 69:10
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
CHROMATES
RADIOLYSIS
LITHIUM COMPOUNDS
TUNGSTATES
ELECTRON BEAMS
EV RANGE 100-1000
KEV RANGE 01-10
PHOTOELECTRON SPECTROSCOPY
ALKALI METAL COMPOUNDS
BEAMS
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTIONS
CHEMISTRY
CHROMIUM COMPOUNDS
DECOMPOSITION
ELECTRON SPECTROSCOPY
ENERGY RANGE
EV RANGE
KEV RANGE
LEPTON BEAMS
OXYGEN COMPOUNDS
PARTICLE BEAMS
RADIATION CHEMISTRY
RADIATION EFFECTS
SPECTROSCOPY
TRANSITION ELEMENT COMPOUNDS
400600* - Radiation Chemistry