Correcting spectra
Should I correct the baseline of my spectrum?
If a baseline is sloped or curved or significantly above zero
absorbance (or below 100% transmittance), a likely cause is how the
sample was prepared. By correcting the baseline, you can often
avoid having to prepare the sample again and collect a new
spectrum.
Correcting a baseline will give you better results when you search
the spectrum against a library, subtract the spectrum from another
spectrum, find peaks in the spectrum or quantify components in the
spectrum.
Collecting a Spectrum (available through Learning OMNIC)...
“Common Problems with IR Spectra”
?
In OMNIC Help Topics find “baseline” in the Index and go to
“Correcting a baseline manually.”
Subtracting,
adding, multiplying
and dividing spectra
How can I subtract a spectrum from another
spectrum?
Use Subtract in the Process menu whenever you want to subtract one
spectrum from another. Subtract is commonly used to remove
spectral features of solvent residues or pure components from the
spectrum of a mixture of compounds.
Select the spectrum from which you want to subtract spectral
features; this is the sample spectrum. Then hold down the Control
key and select the spectrum with the features you want to subtract
from the sample spectrum; this is the reference spectrum.
Note
Subtract is available only when two spectra are selected.
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