ETTLINGEN, Germany – February, 2013 – Bruker launches a very powerful method for the automated conversion of FTIR spectra measured in ATR (attenuated total reflection) mode into absorption spectra.
In modern industrial quality control most FTIR spectra are measured by ATR as this approach requires minimal sample preparation. Samples such as powders, pastes or liquids are simply placed on the diamond ATR crystal and analyzed within seconds. The recorded spectra are typically compared against reference libraries to identify the chemical composition of the sample. In the past, many dark samples including polymers and other high carbon black samples were not well suited for diamond or ZnSe ATR. For these samples the accessory or at a minimum the crystal of the ATR would need to be exchanged for a Germanium ATR element which has a higher refractive index than diamond or ZnSe. With Bruker’s new advanced ATR correction method exchange of the ATR crystal is no longer required. This new advanced ATR correction is implemented in Bruker’s latest release of OPUS, version 7.2, which has been released in February 2013 and implemented for all spectrometers. In contrast to conventional ATR correction algorithms which only correct for intensity, Bruker’s advanced ATR correction also corrects for band distortions resulting from anomalous dispersion when the critical angle is exceeded. With this advanced ATR correction method, high quality spectra can be collected from almost all dark materials by ATR with standard crystals made from ZnSe or diamond.
The advanced ATR correction is a powerful tool for use on Bruker’s ALPHA-P FTIR spectrometer, which includes a singles bounce diamond ATR. This very compact FTIR system is well established for quality control in manufacturing, polymer studies, chemicals, and organic coatings. With the advanced ATR correction method it is no longer necessary to exchange the ATR crystal when analyzing highly absorbing materials such as carbon filled polymers. For applications in R&D, the advanced ATR correction method can be readily applied to data collected on Bruker’s TENSOR and VERTEX FTIR spectrometers as well.