Vibrational resonance spectroscopy

Infrared and Raman spectroscopy each probe vibrational motion, but respond to a different manifestation of it. Infrared spectroscopy is sensitive to a change in the dipole moment as a function of the vibrational motion, whereas Raman spectroscopy probes the change in polarizability as the molecule undergoes vibrations. Resonance Raman spectroscopy also couples to excited electronic states, and can yield fiirtlier infomiation regarding the identity of the vibration. Raman and IR spectroscopy are often complementary, both in the type of systems tliat can be studied, as well as the infomiation obtained. 

Labuda M J and Wright J C 1997 Measurement of vibrationally resonant and the feasibility of new vibrational spectroscopies Phys. Rev. Lett. 79 2446-9... 

No molecule is completely rigid and fixed. Molecules vibrate, parts of a molecule may rotate internally, weak bonds break and re-fonn. Nuclear magnetic resonance spectroscopy (NMR) is particularly well suited to observe an important class of these motions and rearrangements. An example is tire restricted rotation about bonds, which can cause dramatic effects in the NMR spectrum (figure B2.4.1). 

I. N. Levine (1975) Molecular Spectroscopy (John Wiley Sons, New York). A survey of the theory of rotational, vibrational, and electronic spectroscopy of diatomic and polyatomic molecules and of nuclear magnetic resonance spectroscopy. 

The physico-chemical changes induced in polymers following exposure to radiation can be studied by a range of spectroscopic techniques. Recent developments in instrumentation and data analysis procedures in electronic, vibrational and magnetic resonance spectroscopies have provided considerable new insights into polymer structure and behaviour. The application of these spectroscopic methods in polymer studies are reviewed with emphasis on their utility in investigations of radiation effects on macromolecules. 

N. Seurre, J. Sepiof, F. Lahmani, A. Zehnacker Rentien, and K. Le Barbu Debus, Vibrational study of the So and Si states of 2 naphthyl 1 ethanol/ (water)2 and 2 naphthyl 1 ethanol/ (methanol)2 complexes by IR/UV double resonance spectroscopy. Phys. Chem. Chem. Phys. 6, 4658 4664 (2004). 

Bryant, G. P., Yiang, Y., and Grant, E. R. (1992), Triple-Resonance Spectroscopy of the Higher Excited States of N02. Trends in the Mode Dependence of Vibrational Autoionization via Asymmetric Stretch versus Symmetric Stretch and Bend, J. Chem. Phys. 96,4827. 

The techniques considered in this chapter are infrared spectroscopy (or vibrational spectroscopy), nuclear magnetic resonance spectroscopy, ultraviolet-visible spectroscopy (or electronic spectroscopy) and mass spectrometry. Absorption of infrared radiation is associated with the energy differences between vibrational states of molecules nuclear magnetic resonance absorption is associated with changes in the orientation of atomic nuclei in an applied magnetic field absorption of ultraviolet and visible radiation is associated with changes in the energy states of the valence electrons of molecules and mass spectrometry is concerned... 

Often, these adducts were characterized by vibrational spectroscopy, and Raman spectroscopic investigations were particularly informative and indicative for the occurrence of E E bonds. Some E E stretching vibrations vE E are summarized in Table I. They nicely show the expected dependency of vE E on the atomic masses of the respective elements and on the masses of the substituents. Some compounds were further characterized by nuclear quadrupole resonance spectroscopy, which gave indications for phase transfer processes and for the extent of electron transfer from the ligands to Ga or In atoms.15,16 Most helpful for the discussion of the constitution and conformation of these subhalides are the results of X-ray... 

Vibrational product state distributions have been obtained for reactions studied in crossed molecular beams using the technique of beam electric resonance spectroscopy [109]. This method uses the focusing action of electric quadrupole and dipole fields to measure the radio frequency Stark spectrum of the reaction products, which must possess a dipole moment. This has restricted this technique to reactions producing alkali halides. 

Okumura K, Tanimura Y. The (2w + l)th-order off-resonant spectroscopy from the (n + 1 )th-order anharmonicities of molecular vibrational modes in the condensed phase. J Chem Phys 1997 106 1687-1698. 

Aramaki et al.30 examined the photochromic reactions of spirooxazines by picosecond time-resolved Raman spectroscopy. Vibrational resonance Raman spectra of the merocyanine isomer(s) recorded over a 50-ps-1.5-ns interval did not change. This indicated that the open ring opening to form a stable merocyanine isomer or the distribution of isomers31 was complete within 50 ps and that the isomer(s) distribution remained unchanged for at least 1.5 ns. 

Vibration spectroscopy frequency and intensity changes in infrared and Raman spectra Nuclear magnetic resonance spectroscopy large H chemical shifts, small, 3C chemical shifts Internuclear H - - A distances less than van der Waals, but greater than covalent or ionic... 

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