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Spectroscopic applications

Yan Y X, Gamble E B and Nelson K A 1985 Impulsive stimulated Raman scattering general importance in femtosecond laser pulse interactions with matter, and spectroscopic applications J. Chem. Phys. 83 5391-9... [Pg.1230]

Time-of-flight mass spectrometers have been used as detectors in a wider variety of experiments tlian any other mass spectrometer. This is especially true of spectroscopic applications, many of which are discussed in this encyclopedia. Unlike the other instruments described in this chapter, the TOP mass spectrometer is usually used for one purpose, to acquire the mass spectrum of a compound. They caimot generally be used for the kinds of ion-molecule chemistry discussed in this chapter, or structural characterization experiments such as collision-induced dissociation. Plowever, they are easily used as detectors for spectroscopic applications such as multi-photoionization (for the spectroscopy of molecular excited states) [38], zero kinetic energy electron spectroscopy [39] (ZEKE, for the precise measurement of ionization energies) and comcidence measurements (such as photoelectron-photoion coincidence spectroscopy [40] for the measurement of ion fragmentation breakdown diagrams). [Pg.1354]

A current description of femtosecond laser teclmology, with a discnssion of nltrafast spectroscopic applications. [Pg.2003]

Nevertheless, DFT has been shown over the past two decades to be a fairly robust theory that can be implemented with high efficiency which almost always surpasses HF theory in accuracy. Very many chemical and spectroscopic problems have been successfully investigated with DFT. Many trends in experimental data can be successfully explained in a qualitative and often also quantitative way and therefore much insight arises from analyzing DFT results. Due to its favorable price/performance ratio, it dominates present day computational chemistry and it has dominated theoretical solid state physics for a long time even before DFT conquered chemistry. However, there are also known failures of DFT and in particular in spectroscopic applications one should be careful with putting unlimited trust in the results of DFT calculations. [Pg.147]

Arthur Moritz SchOnflies, German mathematician (1853-1928). The SchOnflies symbols are employed io spectroscopic applications, while in crystallography the international, or Hennann-Maugiur) notation is used. [Pg.91]

In spectroscopic applications the letters g and u (German Gerade, Ungerade) are used to specify the symmetry of the functions under the inversion operation, x — —x. Note that the normalization constant is given by y/TJI, as before. [Pg.265]

Molecular spectra can be analyzed for spectrometric or for spectroscopic purposes. The term spectrometric usually refers to compound identification (linking a signal to a known structure) and to the determination of its concentration. The term spectroscopic stands for interpretation of the spectrum in terms of structure (chemical, electronic, nuclear, etc.). In this chapter we will look as some theoretical and practical aspects of a key spectrometric application of bioEPR, namely, the determination of the concentration of paramagnets, also known as spin counting. Subsequently, we consider the generation of anisotropic powder EPR patterns in the computer simulation of spectra, a basic technique that underlies both spectrometric and spectroscopic applications of bioEPR. [Pg.95]

Obviously, however, someone needs to do more research on that topic. I contacted Philip Brown and asked him about this topic. Unfortunately, linearity per se is not of interest to him the emphasis of the paper he wrote was on role of linearity in the wavelength-selection process, not the nonlinearity itself. Furthermore, in the years since that paper appeared, his interests have changed and he is no longer pursuing spectroscopic applications. [Pg.468]

This is essentially the solution generated by solving simultaneous equations This is fine if we can rely on simultaneous equations for the solution to our data. In the general case, however, matrix A will not have the same numbers of rows and columns in fact, it is often necessary for matrix A to contain data from more samples than there are variables (i.e., wavelengths, in spectroscopic applications). Therefore we cannot simply compute the inverse of matrix A, because only square matrices can be inverted. Therefore we proceed by multiplying equation 69-3 by AT ... [Pg.473]

Most chemical applications of lasers have fallen into three categories. Firstly, spectroscopic applications have utilized... [Pg.454]

A family of vacuum-tube MMW sources is based on the propagation of an electron beam through a so-called slow-wave or periodic structure. Radiation propagates on the slow-wave structure at the speed of the electron beam, allowing the beam and radiation field to interact. Devices in this category are the traveling-wave tube (TWT), the backward-wave oscillator (BWO) and the extended interaction oscillator (EIO) klystron. TWTs are characterized by wide bandwidths and intermediate power output. These devices operate well at frequencies up to 100 GHz. BWOs, so called because the radiation within the vacuum tube travels in a direction opposite to that of the electron beam, have very wide bandwidths and low output powers. These sources operate at frequencies up to 1.3 THz and are extensively used in THZ spectroscopic applications [10] [11] [12]. The EIO is a high-power, narrow band tube that has an output power of 1 kW at 95 GHz and about 100 W at 230 GHz. It is available in both oscillator and amplifier, CW and pulsed versions. This source has been extensively used in MMW radar applications with some success [13]. [Pg.248]

Spectroscopic applications usually require us to go beyond single-point electronic energy calculations or structure optimizations. Scans of the potential energy hypersurface or at least Taylor expansions around stationary points are needed to extract nuclear dynamics information. If spectral intensity information is required, dipole moment or polarizability hypersurfaces [202] have to be developed as well. If multiple relevant minima exist on the potential energy hyper surface, efficient methods to explore them are needed [203, 204],... [Pg.23]

It is already a fact that lasers are replacing conventional lamps in a great variety of spectroscopic applications. The origin of this substitution lies in their superior performance over incoherent light in many experimental situations. Many spectroscopic experiments have been improved, and moreover new techniques have been developed due to the particular advantages provided by lasers. The characteristics of laser radiation on their own constitute real advantages and justify their widespread use in many applications. [Pg.45]

Some of these spectroscopic applications of lasers will be discussed in this review article, the experiments described exemplifying the laser s potential as a tool for spectroscopists. [Pg.3]

These techniques are extremely important in investigations of very fast processes and some spectroscopic applications will be discussed in Section III.3, 5 and 6. [Pg.11]

Like SNV, this pretreatment method [1,21] is a sample-wise scaling method, which has been effectively used in many spectroscopic applications where multiplicative variations are present. However, unlike SNV, the MSC correction parameters are not the mean and standard deviation of the variables in the spectrum x, but rather the result of a linear lit of a reference spectrum x f to the spectrum. The MSC model is given by the following equation ... [Pg.372]


See other pages where Spectroscopic applications is mentioned: [Pg.1972]    [Pg.17]    [Pg.450]    [Pg.113]    [Pg.456]    [Pg.468]    [Pg.249]    [Pg.30]    [Pg.12]    [Pg.14]    [Pg.16]    [Pg.18]    [Pg.20]    [Pg.22]    [Pg.24]    [Pg.26]    [Pg.28]    [Pg.30]    [Pg.32]    [Pg.34]    [Pg.36]    [Pg.38]    [Pg.40]    [Pg.42]    [Pg.44]    [Pg.46]    [Pg.48]    [Pg.50]    [Pg.52]    [Pg.54]    [Pg.56]    [Pg.58]    [Pg.88]   
See also in sourсe #XX -- [ Pg.57 ]

See also in sourсe #XX -- [ Pg.142 , Pg.145 ]

See also in sourсe #XX -- [ Pg.57 , Pg.839 ]




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Applications of Laser-Induced Time-Resolved Spectroscopic Techniques

Applications of Spectroscopic Methods

Applications other spectroscopic methods

Configuration interaction spectroscopic applications

Helen F. Gleeson 4 Liquid Crystals as Solvents for Spectroscopic, Chemical Reaction, and Gas Chromatographic Applications

Laser-spectroscopic applications

Near-infrared spectroscop applications

Neutron spectroscopic applications

Nuclear magnetic resonance spectroscop analytical applications

Observation of a Penetration Depth Gradient in ATR FT-IR Spectroscopic Imaging Applications

Spectroscopic Applications of Lasers

Spectroscopic Methods Applicable to Different Sample Sizes

Spectroscopic biological application

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