Synchrotron far infrared spectroscopy

A new development is the elaboration of synchrotron far infrared spectroscopy (SFIRS) for adsorption shid-ies [124]. 

Melendres and Hahn [173] have extended the vertical spatial resolution of in situ infrared spectroscopy by employing synchrotron radiation in the far-infrared region of the spectrum, (synchrotron far infrared spectroscopy, SFIRS), to study metal-adsorbate bonds. The authors exploited the Kretschmann configuration to improve the sensitivity of the technique, and studied the adsorption of Cl and Br at the thin Au film working electrode. They observed bands near 263 and 187 cm for the Au—Cl and Au—Br stretches, respectively, in good agreement with the SERS data of Gao and Weaver [174]. 

The world has a growing number of synchrotron infrared beamlines and their use has also rapidly grown across a wide number of scientific applications. This review is far from comprehensive, but we hope it has highlighted several of the exciting recent developments in the field and the application of these sources to a wide variety of materials science. And in the near future we anticipate several advances, which will further increase the uses and capabilities of synchrotron, based infrared spectroscopies and microscopies. To find out more about how synchrotron infrared techniques may play a role in your research, we encourage you to contact one of the many friendly infrared beamline scientists at a synchrotron light source near you [2]. 

The plant availability of phosphates depends on their chemical form, hence analytical techniques to quickly determine the mineral phases are necessary. Hydrated forms (e.g., Ca(H2P04)2-H20 and CaHPO -2H20) normally show better plant availability than non-hydrated phosphates (e.g., Ca5(P04)30H). Previously, single beam mid- and far-infrared spectroscopy was successfully applied for the analysis of P-phases in SSA-based fertilizer [88]. Using spectroscopic imaging methods with a lateral resolution down to the diffraction limit of 5-10 pm for synchrotron radiation infrared microspectroscopy, almost pure mineral phases are detectable. 

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