*Graphical representation of a single bounce AT*

In this issue: Learn about the basic theory of attenuated total reflection (ATR) spectroscopy.

ATR has become the dominant method for the collection of an FTIR spectrum of solid materials. It has little to no sample preparation and is effective at both qualitative and quantitative measurements.

Compared to the older transmission methods, such as KBr important differences emerge. An ATR spectrum is not directly comparable to a transmission spectrum, although software algorithms are available in most commercial spectrometers capable of converting an ATR spectrum into a transmission-like spectrum should the analyst wish to compare them.

This note outlines the basics of the ATR method, providing the analyst with the information they require to gain the most out of the technique.