1
iS50 ATR Module
Thermo Scientific
iS50 ATR Module User Guide
9
Compatible Samples
The ATR module can be used to analyze any sample that allows good contact with the surface
of the crystal and has an index of refraction less than 2.0 (most organic materials range
between 1.3 and 1.7).
ATR is an excellent technique for measuring the composition of liquids, powders and bulk
solids or the surface properties of a layered solid. Because the effective pathlength is short,
ATR is especially useful for analyzing strongly absorbing or thick samples which often
produce large unreadable peaks when measured directly by infrared transmission. The ATR
technique also eliminates the sample preparation required to run these types of samples by
transmission.
For a detailed list of materials that are easy to measure by ATR, refer to the document or help
topic titled “
.”
Your First Experiment
This section explains how to configure your ATR workflow and demonstrates how to use the
ATR module to analyze a solid and a liquid sample. These topics are covered:
•
•
Measuring a Solid Sample by ATR
•
Measuring a Liquid Sample by ATR
Configuring Your ATR Workflow
The ATR Touch Point has an associated user-configurable workflow that can define
everything from background and sample collection to quantitative analysis and spectral
search. You simply press the Touch Point to start the workflow. The Touch Point can also be
used to respond to prompts in the software while the workflow is running.
To configure your ATR workflow
1. Start OMNIC software.
The OMNIC window is displayed. For information about the OMNIC window, choose
Help > OMNIC Help Topics.
2. Choose the ATR Touch Point button in the software to configure the instrument for ATR
sampling.
NOTICE
Do not use the ATR module to analyze concentrated sulfuric acid (H
2
SO
4
) or
potassium dichromate (K
2
Cr
2
O
7
); they will react with the diamond crystal.
