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Problem
Possible Cause
Solution
A spectrum contains no
peaks.
No sample is in the infrared
beam path.
The sampling cup in a diffuse
reflection experiment is not in
place or is tilted.
An infrared microscope is in
its viewing mode.
A sample film in an ATR
experiment is being held
against the ATR crystal with
uneven pressure or has poor
contact with the crystal.
The resolution is set too low.
Check the sample compartment or
accessory to make sure the sample is
properly positioned in the beam path.
Make sure the cup is properly
positioned in the diffuse reflection
accessory. For more information, view
the appropriate tutorial available
through Sampling Techniques in the
Help menu.
Put the microscope in infrared mode
and collect the spectrum again.
Make sure the sample is held evenly
and has good contact with the crystal.
Set Resolution on the Collect tab of
the Experiment Setup dialog box to a
value that lets you see small peaks.
(Use a lower numerical setting to
achieve higher resolution.)
A spectrum contains
derivative-shaped peaks.
A sample in a diffuse
reflection experiment also has
a specular reflection
component.
The infrared beam was
reflected from (instead of
penetrating) a flat, shiny
sample measured using a
specular reflection accessory.
Correct the spectrum by using Other
Corrections in the Process menu.
(Select Kramers-Kronig.)
Try using a less reflective sample.
152 Thermo Electron Corporation