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Spectral analysis quantum-mechanical

Windaisy Allows you to export the evaluated chemical shifts and coupling constants as starting values to the WIN-DAISY program for a more rigorous quantum mechanical spectral analysis. [Pg.108]

Time-Dependent Quantum-Mechanical Spectral Analysis 149... [Pg.145]

Time-Independent Quantum-Mechanical Spectral Analysis 154... [Pg.145]

TIME-DEPENDENT QUANTUM-MECHANICAL SPECTRAL ANALYSIS... [Pg.149]

The nonstationary quantum-mechanical spectral analysis uses the time-dependent Schrodinger equation [2] ... [Pg.149]

Quantum-mechanical spectral analysis can advantageously to use the formalism of the Green function Q co), which is a matrix element of a resolvent... [Pg.152]

Molecular spectroscopy offers a fiindamental approach to intramolecular processes [18, 94]. The spectral analysis in temis of detailed quantum mechanical models in principle provides the complete infomiation about the wave-packet dynamics on a level of detail not easily accessible by time-resolved teclmiques. [Pg.2141]

We examine the derivation of information about molecular structure and properties from analysis of pure rotational and vibration-rotational spectral data of diatomic molecular species on the basis of Dunham s algebraic formalism, making comparison with results from alternative approaches. According to an implementation of computational spectrometry, wave-mechanical calculations of molecular electronic structure and properties have already played an important role in spectral reduction through interaction of quantum chemistry and spectral analysis. [Pg.253]

The basic theories of physics - classical mechanics and electromagnetism, relativity theory, quantum mechanics, statistical mechanics, quantum electrodynamics - support the theoretical apparatus which is used in molecular sciences. Quantum mechanics plays a particular role in theoretical chemistry, providing the basis for the valence theories which allow to interpret the structure of molecules and for the spectroscopic models employed in the determination of structural information from spectral patterns. Indeed, Quantum Chemistry often appears synonymous with Theoretical Chemistry it will, therefore, constitute a major part of this book series. However, the scope of the series will also include other areas of theoretical chemistry, such as mathematical chemistry (which involves the use of algebra and topology in the analysis of molecular structures and reactions) molecular mechanics, molecular dynamics and chemical thermodynamics, which play an important role in rationalizing the geometric and electronic structures of molecular assemblies and polymers, clusters and crystals surface, interface, solvent and solid-state effects excited-state dynamics, reactive collisions, and chemical reactions. [Pg.428]

S. A. Rice My answer to Prof. Manz is that, as I indicated in my presentation, both the Brumer-Shapiro and the Tannor-Rice control schemes have been verified experimentally. To date, control of the branching ratio in a chemical reaction, or of any other process, by use of temporally and spectrally shaped laser fields has not been experimentally demonstrated. However, since all of the control schemes are based on the fundamental principles of quantum mechanics, it would be very strange (and disturbing) if they were not to be verified. This statement is not intended either to demean the experimental difficulties that must be overcome before any verification can be achieved or to imply that verification is unnecessary. Even though the principles of the several proposed control schemes are not in question, the implementation of the analysis of any particular case involves approximations, for example, the neglect of the influence of some states of the molecule on the reaction. Moreover, for lack of sufficient information, our understanding of the robustness of the proposed control schemes to the inevitable uncertainties introduced by, for example, fluctuations in the laser field, is very limited. Certainly, experimental verification of the various control schemes in a variety of cases will be very valuable. [Pg.93]

Dz. Belkic, Quantum-Mechanical Signal Processing and Spectral Analysis, Institute of Physics Publishing, Series in Atomic and Molecular Physics, Bristol, 2005. [Pg.112]

Spectral analysis of the emission, however, showed, that it was actually delayed phosphorescence, i.e. (PhjNH) produced in the ion-electron recombination must be in a triplet state °. esr studies on transients produced in the photolysis of di-diphenylamine in alcohols at low temperatures also confirmed the existence of (PhjNH) and demonstrated an overall 2-photon absorption mechanism involving a triplet-triplet transition The quantum yield of phosphorescence is 0.05. ... [Pg.641]

Modern spectral analysis has largely lost track of the quantum mechanical foundation of NMR spectroscopy. As a result, many common NMR phenomena must be taken on faith. Without knowledge of the quantum mechanical treatment, however, one cannot answer common questions such as the following ... [Pg.302]

An approach based on the sequential use of Monte Carlo simulation and Quantum Mechanics is suggested for the treatment of solvent effects with special attention to solvatochromic shifts. The basic idea is to treat the solute, the solvent and its interaction by quantum mechanics. This is a totally discrete model that avoids the use of a dielectric continuum. Statistical analysis is used to obtain uncorrelated structures. The radial distribution function is used to determine the solvation shells. Quantum mechanical calculations are then performed in supermolecular structures and the spectral shifts are obtained using ensemble average. Attention is also given to the case of specific hydrogen bond between the solute and solvent. [Pg.89]


See other pages where Spectral analysis quantum-mechanical is mentioned: [Pg.250]    [Pg.250]    [Pg.69]    [Pg.301]    [Pg.397]    [Pg.113]    [Pg.254]    [Pg.275]    [Pg.310]    [Pg.320]    [Pg.113]    [Pg.106]    [Pg.363]    [Pg.152]    [Pg.34]    [Pg.339]    [Pg.256]    [Pg.6273]    [Pg.97]    [Pg.579]    [Pg.41]    [Pg.1]    [Pg.69]   
See also in sourсe #XX -- [ Pg.152 ]




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