Thermo Electron Nicolet 380, User Manual

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Comparing spectra
for quality control
QC (Quality Control) libraries let you verify the composition of
materials. These libraries are useful for quality control operations in
which you know what a sample should contain and just need to
verify and document the composition.
Spectra in QC libraries are stored in groups called “compound
types.” This lets you maintain reference spectra that reflect variables
in, or tolerances allowed for, your samples. The software compares
your sample spectrum with the reference spectra in each compound
type and reports the best match from each type.
QC comparisons are also useful for detecting minute differences in
spectra. If you need to detect small changes (in the parts per million
range) in your samples or identify samples that are spectroscopically
very similar, you could create a QC library with as few as one
reference spectrum in each compound type.
In OMNIC Help Topics find “QC comparison” in the Index and go
to the “Performing a QC comparison” topic for more information
about QC comparisons.
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