FTIR Sample Preparation Overview and

Many of the transmission techniques discussed earlier in this chapter were developed over 50-plus years ago and involve a certain amount of skill and sometimes significant amounts of manual sample preparation. Back then labor was cheaper, and it was okay for it to take many minutes or hours for one sample to be analyzed. However, in the 21st century, labor costs are significantly higher, and all labs are under pressure to do more with less to increase profitability. Therefore, the main criterion the author uses to evaluate sample preparation techniques is speed and ease of use. For many samples, reflection techniques are faster and easier than transmission techniques. My approach, then, is that for a given sample I will try reflection techniques first. If the reflection technique works well, it will do so quickly and I can move on to the next sample. If the reflection technique does not work well, I find out quickly so not much time is wasted. Then, I will try one of the transmission techniques appropriate for the particular sample. 

The introduction in the mid-1990s of diamond ATR accessories has revolutionized FTIR sample preparation. The toughness and durability of diamond now means that materials that would have formerly scratched or pressures that would have broken ATR crystals are now tolerated, and all manner of liquids, semi-solids, solids, and powders can be analyzed quickly and easily using this device. For these reasons diamond ATR is the premier type of sample preparation in use today. It does not work well on all 

Solids Specular reflectance, KBr pellets, mulls, DRIFTS, 

Liquids Capillary thin films, sealed liquid cells, ATR 

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