ATR makes mid–infrared liquid analysis possible. The absorptions corresponding to the fundamental vibrations of most organic chemical fall in the mid–infrared region of the spectrum. However, most of these absorptions are far too strong for practical transmission analysis. ATR solves this problem by providing very short effective pathlengths.11, 12 Axiom has pioneered the application of ATR to a wide range of tasks both in the lab and on the process line14, 15 and holds a number of important patents in this field.1, 2, 3 The company’s laboratory ATR product lines are summarized below. Additional ATR probes are included in the Process Line section of this website.
Overview of Mid-Infrared ATR Products (.pdf)
With the DPR-210 or 212 ATR probe, you can perform rapid FTIR analysis on a wide range of samples with virtually no sample handling.1, 2, 3 Mount the probe in the sample compartment of your spectrometer for easy analysis of liquids, pastes, or slurries. And, clean–up is simple, quick, and free from sample retention. Simply rinse the DPR–210 or 212 with a suitable solvent and wipe it off with a soft towel or brush. Interchangeable ATR elements allow you to optimize performance for most chemical systems.
DPR–207 and DMD–270 ATR probes1, 2, 3, 8, 9, 15 feature the small diameter and mounting flexibility required by many research and process development applications. The key to their small diameter and high performance is the use of a single gold lightguide to couple the IR radiation both to the probe tip and back to the instrument. This is combined with a patented design which eliminates stray light due to first surface reflections. For optimum performance, these probes should be used with a liquid nitrogen cooled MCT detector.
Hellma Axiom’s TNL Series "TUNNEL" ATR flow cells4, 5 set the standard for highly accurate, and yet economical, mid–IR liquid analysis. The patented design of these cells insures that all optical rays passing through the cell experience the same number of reflections and nearly the same angle. This results in a very high degree of photometric accuracy and repeatability.13 In addition, the helical flow characteristics insure rapid sample exchange and cleanout.5
Model SM-Alpha1 is an interface module designed to optimize the performance of the Bruker Alpha FTIR spectrometer for use with the Hellma Axiom ATR probes and other mid-infrared sampling equipment. Its unique optical design features an F:4.5 optical beam geometry, which maximizes transmission while allowing an ATR probe to rotate to any desired orientation. The SM-Alpha1 is interchangeable with standard Bruker QuickSnap™ sampling modules.