Spectroscopy solid-state

These limitations have recently been eliminated using solid-state sources of femtosecond pulses. Most of the femtosecond dye laser teclmology that was in wide use in the late 1980s [11] has been rendered obsolete by tliree teclmical developments the self-mode-locked Ti-sapphire oscillator [23, 24, 25, 26 and 27], the chirped-pulse, solid-state amplifier (CPA) [28, 29, 30 and 31], and the non-collinearly pumped optical parametric amplifier (OPA) [32, 33 and 34]- Moreover, although a number of investigators still construct home-built systems with narrowly chosen capabilities, it is now possible to obtain versatile, nearly state-of-the-art apparatus of the type described below Ifom commercial sources. Just as home-built NMR spectrometers capable of multidimensional or solid-state spectroscopies were still being home built in the late 1970s and now are almost exclusively based on commercially prepared apparatus, it is reasonable to expect that ultrafast spectroscopy in the next decade will be conducted almost exclusively with apparatus ifom conmiercial sources based around entirely solid-state systems. 

Flipps KW (2006) Scanning tunneling spectroscopy. In Vij DR (ed) Handbook of applied solid state spectroscopy. Springer, New York, ISBN 0-387-32497-6... 

The interpretation of optical spectra of solids is even more complicated than for atomic and molecular systems, as it requires a previous understanding of their atomic and electronic structure. Unlike liquids and gases, the basic units of solids (atoms or ions) are periodically arranged in long (crystals) or short (glasses) order. This aspect confers particular characteristics to the spectroscopic techniques used to analyze solids, and gives rise to solid state spectroscopy. This new branch of the spectroscopy has led to the appearance of new spectroscopic techniques, which are increasing day by day. 

In any case, it is worthwhile to emphasize the dominant role of optical spectroscopy in the investigation of solids. Indeed, the optical spectroscopy of solids appears as a nice window onto the more general field of solid state spectroscopy. 

A big advantage of the solid-solid technique is the possibility of obtaining complexes that are not obtainable from solution. It must, however, be shown that uniform complexes rather than microcrystalline mixtures occur. Apart from X-ray powder diffraction (which does not properly account for very small crystallites), proof is obtained by solid-state spectroscopy (IR, UV, luminescence) or, in the case of stable radicals, by magnetic susceptibility measurements. The 1 1 and 2 1 complexes 68-72 were prepared by stoichiometric milling and relevant physical properties are collected in Table 3 [20]. 

At the third level, the most detailed partition of luminescence minerals is carried out on the basis of metals in the mineral formulae, hi rare cases we have minerals with host luminescence, such as uranyl minerals, Mn minerals, scheelite, powellite, cassiterite and chlorargyrite. Much more often luminescent elements are present as impurities substituting intrinsic cations if their radii and charges are close enough. Thus, for example, Mn + substitutes for Ca and Mg in many calcium and magnesium minerals, REE + and REE substitutes for Ca, Cr substitutes for AP+ in oxygen octahedra, Ee substitutes for Si in tetrahedra and so on. Luminescence centers presently known in solid-state spectroscopy are summarized in Table 4.2 and their potential substitutions in positions of intrinsic cations in minerals in Table 4.3. 

Scholz F, Lange B (1992) Abrasive stripping voltammetry - an electrochemical solid state spectroscopy of wide applicability. Trends Anal Chem 11 359-367. 

Very recent studies have examined the possibility of using 33S MAS spectroscopy in the study of some structural problems in cementitious materials107 108 and in sulphur speciation in silicate melts.109 Several processes of the deterioration of cements and more generally lapideous materials can be correlated to the stability of sulphate, to changes in the sulphate phase and to the interaction of sulphate ions with water molecules and hydrates.108 Since sulphate anion is one of the species that can be studied more easily by 33S NMR solid-state spectroscopy, this technique can be a valuable tool in studying... 

Considering the state of the matter, NQR is a branch of solid state spectroscopy. Consequently, the NQR frequencies are due to transitions between different energy levels in the solid. 

Babushkina, T. A., Robas, V. I., Semin. G. K., in Radiospektroskopya Tverdogo Tela [Solid State Spectroscopy, Conference Report], p. 221 (eo. Akad. Name SSSR, Sov. po fizike tverdogo tela. Inst, fiziki SO AN SSSR). Moskau Atom zd-at 1967. 

From the outset, it was clear that Si MASNMR resonances were, to some degree, structure-sensitive. The correlation charts of Lippmaa et al (5.9) and our own (7, 10) show a range of values at which a 2 si nucleus in a particular environemnt (Si(0Al) (OSi) with n = 0, 1, 2, 3> or k) was expected to resonate his point emerges clearly from Table 1. In this respect MASNMR is similar to IR, UV and Raman and solution NMR spectroscopies for which there are comparable charts that are constructed, as in 29sI MASNMR, solid-state spectroscopy, largely on the basis of accumulated practical experience, rather than on theoretical calculations. ... 

As a final example, we mention the combination of solid-state spectroscopy (Chapter 15) with imaging. The imaging of solids is difficult because the 7Ys are often too short compared with the time it takes to switch and apply field gradients for slice selection and phase and frequency encoding, while in addition extremely large gradient amplitudes are required to overcome the broad line widths. The time to ramp... 

It is possible to exactly identify and characterize the radical species and chain structures of the reaction intermediates, which are determined by their different reactive or unreactive chain ends. The reactive intermediates are best described by diradical (DR), asymmetric carbene (AC) and dicarbene (DC) oligomer molecules of different lengths. The respective singlet (S = 0), triplet (S = I) or quintet (S = 1) states and their roles in the polymerization process are investigated in detail by solid state spectroscopy. A one-dimensional electron gas model is successfully applied to the optical absorption series of the DR and AC intermediates as well as on the different stable oligomer SO molecules obtained after final chain termination reactions. 

In this article it has been shown, that the low temperature photopolymerization reaction of diacetylene crystals is a highly complex reaction with a manifold of different reaction intermediates. Moreover, the diacetylene crystals represent a class of material which play a unique role within the usual polymerization reactions conventionally performed in the fluid phase. The spectroscopic interest of this contribution has been focussed mainly on the electronic properties of the different intermediates, such as butatriene or acetylene chain structure, diradical or carbene electron spin distributions and spin multiplicities. The elementary chemical reactions within all the individual steps of the polymerization reaction have been successfully investigated by the methods of solid state spectroscopy. Moreover we have been able to analyze the physical and chemical primary and secondary processes of the photochemical and thermal polymerization reaction in diacetylene crystals. This success has been largely due to the stability of the intermediates at low temperatures and to the high informational yield of optical and ESR spectroscopy in crystalline systems. 

The E X E ]T effect, where a doubly degenerate vibrational mode lifts the degeneracy of a doubly degenerate electronic state, is presumably the most extensively investigated vibronic-coupling problem in molecular and solid-state spectroscopy, see [26-28] for reviews. 

A solid-state variant of the DANTE sequence (Fig. 5.3.15) is obtained by replacing the rf pulses and the free precession periods of the original sequence by line-narrowing multi-pulse sequences [Carl, Corl, Flepl, Hep2J. Such DANTE sequences can be used for selective excitation in solid-state spectroscopy (cf Fig. 7.2.8) and for slice selection in solid-state imaging (Fig. 5.3.16). 

In principle, any scheme of multi-dimensional liquid-state or solid-state spectroscopy can be combined with spatial resolution to mD spectroscopic D imaging. However, measurement times rapidly become excessive, so that meaningful applications are quite rare. 

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