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Reference spectra recorded on a Shimadzu 2100
UV-visible spectrometer. The samples are made of solutions of some rare
earth nitrates in a 1cm path length cell. Rare earth salts with their
incomplete filling of 4f orbitals have multibands spectra in the visible
range and are thus used for the calibration of monochromators. |
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A few drops of the Pr, Nd and Sm salts have
been evaporated on a microscope object slide and spectra were recorded
with the microscope spectrometer
described previously. The resolution is not as good as the Shimadzu
instrument because I'm using a large entrance slit ( 2 mm ) to
increase the light throughput of the system. Nevertheless, the resolution
is sufficient for the purpose of the examination of mineral spectra.
The peaks appear at the same wavelength positions after calibration. |
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The resolution can be improved with a 0.5 mm
entrance slit and a higher sampling frequency: 1 point per nm instead of
1point per 2 nm in the previous figure. |