Simultaneous Raman

Temperature-mediated transformations also occur. Ali et al. collected simultaneous Raman spectra and DSC curves of satmeterol xinafoate, detecting two forms [250]. Raman spectroscopy was used to follow the conversions of erythromycin A dihydrate as a function of temperature conditions were identified where the Raman data provided more insights into the kinetics than powder XRD [251]. 

Thierry D, Leygraf C. Simultaneous raman spectroscopy and electrochemical studies of corrosion inhibiting molecules on copper. J Electrochem Soc 1985 132 1009. 

A new coherent chiral Raman spectroscopy that arises when 3m — a) in Eq. (16) is resonant with the angular frequency of a vibration has been proposed by Koroteev [27]. Known as BioCARS, such a spectroscopy could exclusively probe chiral vibrations that are simultaneously Raman and hyper-Raman active [27, 28]. BioCARS has not yet been observed. 

Applied Spectroscopy 52, No.5, May 1998, p.692-701 INVESTIGATIONS OF RADICAL POLYMERISATION AND COPOLYMERISATION REACTIONS IN OPTICALLY LEVITATED MICRODROPLETS BY SIMULTANEOUS RAMAN SPECTROSCOPY, MIE SCATTERING, AND RADIATION PRESSURE MEASUREMENTS Musick J Popp J Trunk M Kiefer W Wurzburg,University... 

Fleischmann, M., Graves, PR., HiU, I.R. and Robinson, J. (1983) Simultaneous Raman spectroscopy and dUferential double layer capacitance measurement of pyridine adsorbed on roughened silver electrodes. Chemical Physics Letters, 98, 503. 

Schneider, M., Winkler, S. and Bruckner, A. (2008). The Influence of Calcination Conditions on Phase Formation in Movtenbox Catalysts A Simultaneous In Situ XRD/Raman Study, SNBL Workshop on Simultaneous Raman-X-Ray Diffraction/Absorption Studies for the In Situ Investigations of Solid State Transformations and Reactions at Non Ambient Conditions, ESRF Grenoble, 18-19 June 2008. 

These equations assume that the optical field is strong and can be treated classically, a perturbative interaction with the sample that begins and ends with the vibrational ground state, and that there are no levels directly resonant with any of the individual frequencies in the pulse (resonant one-photon interactions do not occur). Near-infrared light (800-1400 nm), which is only weakly absorbed by biological tissues, contains frequencies typically well above the vibrational frequencies of molecular bonds, but below the electronic excitation frequencies, and so is suitable for NIVI. These equations give the time evolution of a CARS/CSRS process involving many possible simultaneous Raman-active... 

Ren B, Li W H, Mao B W, Gao J S and Tian Z Q 1996 Optical fiber Raman spectroscopy combined with scattering tunneling microscopy for simultaneous measurements ICORS 96 XVth Int. Conf on Raman Spectroscopy ed S A Asher and P B Stein (New York Wley) pp 1220-1... 

With broad-band pulses, pumping and probing processes become more complicated. With a broad-bandwidth pulse it is easy to drive fundamental and overtone transitions simultaneously, generating a complicated population distribution which depends on details of pulse stmcture [75], Broad-band probe pulses may be unable to distinguish between fundamental and overtone transitions. For example in IR-Raman experiments with broad-band probe pulses, excitation of the first overtone of a transition appears as a fundamental excitation with twice the intensity, and excitation of a combination band Q -t or appears as excitation of the two fundamentals 1761. 

A schematic of a PL system layout is shown in Figure 5. This optical system is very similar to that required for absorption, reflectance, modulated reflectance, and Raman scattering measurements. Many custom systems are designed to perform several of these techniques, simultaneously or with only small modifications. 

Graphite exhibits strong second-order Raman-active features. These features are expected and observed in carbon tubules, as well. Momentum and energy conservation, and the phonon density of states determine, to a large extent, the second-order spectra. By conservation of energy hut = huty + hbi2, where bi and ill) (/ = 1,2) are, respectively, the frequencies of the incoming photon and those of the simultaneously excited normal modes. There is also a crystal momentum selection rule hV. = -I- q, where k and q/... 

Thus in the presence of an excess of NH4+, which suppresses this forward reaction, and counteranions such as NOa" and C104, which have little tendency to coordinate, complexes such as [Hg(NH3)4] +, [Hg(L-L)2] + and even [Hg(L-L)3] + (L-L = en, bipy, phen) can be prepared. But, in the absence of such precautions, amino, or imino-compounds are likely to be formed, often together. Because of this variety of simultaneous reactions and their dependence on the precise conditions, many reactions between Hg and amines, although first performed by alchemists in the Middle Ages, remained obscure until the application of X-ray crystallography and, still more recently, spectroscopic techniques such as nmr, infrared and Raman. 

It can readily be appreciated that in the absence of any knowledge regarding the differential polarizability tensor, it is a difficult exercise to obtain precise information from the Raman measurements. However, if r is known, Equations (19) are six linear simultaneous Equations in the six quantities (ot2I0N0) 1, P)0o> P220) PIoo> P420 and... 

The 520 nm absorption of S4 has also been observed in the spectrum of certain red-colored ultramarine samples [21] the assignment of this band to the C2V isomer of 4is supported by the simultaneously observed Raman line at 678 cm which represents the symmetrical stretching vibration of the terminal SS bonds of this molecule (see Table 1 below). 

Leopold et al. and Nyholm et al. have investigated this oscillatory system by in situ confocal Raman spectroscopy [43], and in situ electrochemical quartz crystal microbalance [44], and in situ pH measurement [45] with the focus being on darification of the osdllation mechanism. Based on the experimental results, a mechanism for the oscillations was proposed, in which variations in local pH close to the electrode surface play an essential role. Cu is deposited at the lower potentials ofthe oscillation followed by a simultaneous increase in pH close to the surface due to the protonation... 

Proniewicz LM, Paeng IR, Nakamoto K. 1991. Resonance raman spectra of two isomeric dioxygen adducts of iron(II) porphyrins and rr-cation radical and nonradical oxoferryl porphyrins produced in dioxygen matrixes Simultaneous observation of more than seven oxygen isotope sensitive bands J Am Chem Soc 113 3294. 

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