ChemInform Abstract (16 refs.).

The advent of new infrared sampling accessories has allowed in situ study of organometallic systems under conditions that were previously not readily accessible. The techniques of Cylindrical Internal Reflectance (CIR) and Diffuse Reflectance spectroscopies are described herein. The CIR phenomenon was employed in three different apparatus. Two different high pressure CIR cells were used to study reactions homogeneously catalyzed by [μ-HW 2 (CO)10]-. Low temperature reactions of Mo and W complexes were studied using an ambient pressure CIR cell. The diffuse reflectance technique was employed to study powdered samples of Ru carbonyl complexes supported on A1 2 O 3 .It would be a vast understatement to assert that infrared spectro scopy has played a major role in the characterization of organo metallic derivatives, in particular metal carbonyls (1,2). Hence, a discussion of the role of infrared spectroscopy in organometallic chemistry and catalysis in our introductory comments will be avoided. Nevertheless, it is unquestionably true that the enhanced signal/noise available via FTIR has dramatically changed IR spec troscopy. As the technology has changed, the accessories for sampling have changed (3). These in turn have resulted in a significant impact on the type and quality of experiments that can be readily performed.We wish to describe in this chapter some of the new and innov ative infrared accessories commercially available to the exper imental chemist. All of the infrared items described herein were obtained from Spectra Tech, Inc. (652 Glenbrook Road, P. 0. Box 2190-G, Stanford, CT 06906, Ph. (800)243-9186).The conditions for which we have demonstrated the use of these devices involving in situ infrared spectroscopy include the following:• High pressure and high temperature solution phase reactions carried out in both batch-mode or flow-through reactors.