PN 350-007660-07
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8
Digital Force Adapter Usage
Choosing a Press Tip
The success of an ATR measurement depends mostly on the quality of the contact between the sample
and the crystal. Since there is an infinite number of sample shapes and types, a single configuration of
the sample press tip may not be adequate. For this reason, the MIRacle and GladiATR pressure clamps
are designed to accept three different anvil attachments, providing the best possible configuration for
any given sample type. After installing the load cell assembly, any of the sample press tips (swivel, flat,
or concave) originally shipped with the High-Pressure Clamp may be used.
The
swivel tip
features an end cap mounted onto a small ball joint. Such designs allow the pressure tip
to move and adjust its position to the shape of the sample and maintain the sample position parallel to
the crystal surface. This tip allows for better positioning and optimal contact of thin materials with the
crystal surface. The swivel tip is used with irregularly shaped samples, films, and semi-rigid polymers.
The
flat tip
attachment is a straight metal barrel and it may be used when analyzing powdered samples,
rubber samples, and other elastic polymers. Please keep in mind that the depth of penetration of an ATR
crystal is only in the range of 0.5 to 2 microns, and even a small departure from intimate contact with
the crystal will affect the magnitude of the sample absorption.
The
concave tip
was developed specifically to work with large beads and polymer pellets. The tip
features a concave surface, which does not allow the sample to escape from underneath the press. It
also forces the sample to stay in the center of the crystal, assuring the best possible contact.
After choosing an appropriate press tip, attached it to the load cell assembly. The
7.8 mm ATR press tip
must be used with the Three-Reflection MIRacle plate.
Swivel Tip Flat Tip Concave Tip
