Fourier transform microwave spectroscopy FTMW

Fourier transform microwave (FTMW) spectroscopy is very similar to nuclear magnetic resonance, except it probes rotational levels of molecules,... 

Chtrped-Pulse Fourier Transform Microwave Spectroscopy (CP-FTMW) Coupled... 

Laser-Ablation Molecular-Beam Fourier Transform Microwave (LA-MB-FTMW) Spectroscopy... 

Similar to 2DR, ribose (C5H5O5) is one of the most important monosaccharides since it constitutes a subunit of the backbone of RNA. NMR studies have shown that ribose in solution is a mixture of a- and p-pyranose and a- and p-furanose forms, the p-pyranose form being predominant. The recently settled crystal structures have shown that the a- and P-pyranose forms are present in the solid phase [239-243]. The structure in the gas phase has been experimentally investigated using a laser ablation molecular beam Fourier transform microwave spectroscopy (LA-MBFTMW) technique [62]. The high resolution rotational spectrum has provided structural information on a total of six rotamers of ribose, three belonging to the a-pyranose forms and other three to the P-pyranose forms. Recently, D-ribose (m.p. 95°C) has been submitted to a laser ablation broadband (CP-FTMW) spectroscopic study and eight conformers (two new a-pyranose forms) have been identified. A broadband section of the spectra is shown in Fig. 35 and the detected conformers depicted in Fig. 36. 

The future perspectives of this research area depend heavily on the application of CP-FTMW spectrometers, which have changed the scope of rotational spectroscopy in recent years. Chirped-pulse Fourier-transform microwave spectroscopy, combined with laser ablation, opens a new era in the investigation of isolated biomolecules, as can be shown by its application to carbohydrates as discussed in this chapter. The broad frequency and large dynamic range make it possible to extend the range of detectable conformers to less stable forms and to access structural determinations in molecular systems of increasingly larger sizes from measurements of heavy atom ( C, 0) isotopes detected in natural abun-... 

Meth. MW FTMW MBER LaSt IRIRDR IRMWDR method of measurement for jj, microwave spectroscopy Fourier transformation microwave spectroscopy molecular beam electric resonance Laser Stark spectroscopy infrared-infrared double resonance infrared-microwave double resonance... 

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