Resonance Raman spectroscopy vapors

Heating of certain alkali halides with elemental sulfur also produces colored materials containing the anions 82 or 83 which replace the corresponding halide ions. For example, NaCl and KI crystals when heated in the presence of sulfur vapor incorporate di- and trisulfide monoanions [116-119] which can be detected, inter alia, by resonance Raman spectroscopy [120, 121] ... 

Sulfur vapor, saturated and unsaturated, has been investigated by UV-Vis spectroscopy [19], by mass spectrometry (see below), by resonance Raman spectroscopy [20-23], as well as by a sophisticated mathematical analysis [24] of carefully performed pressure measurements as a function of temperature and total sulfur concentration [25-27]. It was concluded that the vapor consists of all molecules from S2 to Ss in temperature- and pressure-dependent equilibria of the following type ... 

As beautiful as this suggestion might be, significantly more must be done to confirm it than to observe that the combination of sixty carbon atoms can be produced in greater abundance than other numbers. Unfortunately, the laser vaporization supersonic cluster beam technique does not produce enough material to perform direct structural techniques like x-ray crystallography or even indirect (but often decisive) experiments such as infrared or Raman spectroscopy, or nuclear magnetic resonance. 

Two separate samples of NasCgo were prepared by direct reaction of Ceo with sodium metal vapor, and subjected to different annealing times of 10 16 days. C and Na solid-state NMR, along with elemental analysis, powder XRD and Raman spectroscopy, were used to characterise both samples. Na and C solid-state NMR spectra of the two samples are significantly different, suggesting a relationship between annealing times and the final structure of the alkali fulleride. Na VTMAS NMR experiments reveal the existence of two or three distinct Na species and reversible temperature-dependent diffusion of sodium ions between octahedral and tetrahedral interstitial sites. C MAS NMR experiments are used to identify resonances corresponding to free Ceo and fulleride species. ... 

The modern electronic industry has played a very important role in the development of instrumentation based on physical-analytical methods As a result, a rapid boom in the fields of infrared, nuclear magnetic resonance (NMR), Raman, and mass spectroscopy and vapor-phase (or gas-liquid) chromatography has been observed. Instruments for these methods have become indispensable tools in the analytical treatment of fluonnated mixtures, complexes, and compounds The detailed applications of the instrumentation are covered later in this chapter. 

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