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Electron absorption

This spectrum is called a Raman spectrum and corresponds to the vibrational or rotational changes in the molecule. The selection rules for Raman activity are different from those for i.r. activity and the two types of spectroscopy are complementary in the study of molecular structure. Modern Raman spectrometers use lasers for excitation. In the resonance Raman effect excitation at a frequency corresponding to electronic absorption causes great enhancement of the Raman spectrum. [Pg.340]

Perhaps the more conventional approach to electronic absorption spectroscopy is cast in the energy, rather than in the time domain. It is straightforward to show that equation (Al.6.87) can be rewritten as... [Pg.247]

The observation of a bend progression is particularly significant. In photoelectron spectroscopy, just as in electronic absorption or emission spectroscopy, the extent of vibrational progressions is governed by Franck-Condon factors between the initial and final states, i.e. the transition between the anion vibrational level u" and neutral level u is given by... [Pg.879]

RRS has also introduced the concept of a Raman excitation profile (REPy for thefth mode) [46, 4lZ, 48, 49, 50 and M]. An REP. is obtained by measuring the resonance Raman scattering strength of thefth mode as a fiinction of the excitation frequency [, 53]. Flow does the scattering intensity for a given (thefth) Raman active vibration vary with excitation frequency within an electronic absorption band In turn, this has led to transfomi theories that try to predict... [Pg.1200]

One group has successfiilly obtained infonnation about potential energy surfaces without measuring REPs. Instead, easily measured second derivative absorption profiles are obtained and linked to the fiill RRS spectrum taken at a single incident frequency. In this way, the painstaking task of measuring a REP is replaced by carefiilly recording the second derivative of the electronic absorption spectrum of the resonant transition [, 59],... [Pg.1201]

Almost every modem spectroscopic approach can be used to study matter at high pressures. Early experiments include NMR [ ], ESR [ ] vibrational infrared [33] and Raman [ ] electronic absorption, reflection and emission [23, 24 and 25, 70] x-ray absorption [Tf] and scattering [72], Mossbauer [73] and gems analysis of products recovered from high-pressure photochemical reactions [74]. The literature contains too many studies to do justice to these fields by describing particular examples in detail, and only some general mles, appropriate to many situations, are given. [Pg.1961]

The development of ultrafast spectroscopy has paralleled progress in the teclmical aspects of pulse fomiation [Uj. Because mode-locked laser sources are tunable only with diflSculty, until recently the most heavily studied physical and chemical systems were those that had strong electronic absorption spectra in the neighbourhood of conveniently produced wavelengths. [Pg.1968]

Pump-probe absorption experiments on the femtosecond time scale generally fall into two effective types, depending on the duration and spectral width of the pump pulse. If tlie pump spectrum is significantly narrower in width than the electronic absorption line shape, transient hole-burning spectroscopy [101. 102. 103. 104. 105. 106. 107. 108. 109. 110. 111. 112 and 113] can be perfomied. The second type of experiment, dynamic absorption spectroscopy [57, 114. 115. 116. 117. 118. 119. 120. 121 and 122], can be perfomied if the pump and probe pulses are short compared to tlie period of the vibrational modes that are coupled to the electronic transition. [Pg.1979]

GUlam and Stem, An Introduction to Electronic Absorption Spectroscopy in Organic Chemistry, 1954 (Arnold). [Pg.1150]

You can use Cl to predict electronic spectra. Since the Cl wave function provides ground state and excited state energies, you can obtain electronic absorption frequencies from the differences between the energy of the ground state and the excited states. [Pg.39]

Table 7.9 Electronic Absorption Bands for Representative Chromophores Table 7.10 Ultraviolet Cutoffs of Spectrograde Solvents Table 7.11 Absorption Wavelength of Dienes Table 7.12 Absorption Wavelength of Enones and Dienones Table 7.13 Solvent Correction for Ultraviolet-Visible Spectroscopy Table 7.14 Primary Bands of Substituted Benzene and Heteroaromatics Table 7.15 Wavelength Calculation of the Principal Band of Substituted Benzene Derivatives... Table 7.9 Electronic Absorption Bands for Representative Chromophores Table 7.10 Ultraviolet Cutoffs of Spectrograde Solvents Table 7.11 Absorption Wavelength of Dienes Table 7.12 Absorption Wavelength of Enones and Dienones Table 7.13 Solvent Correction for Ultraviolet-Visible Spectroscopy Table 7.14 Primary Bands of Substituted Benzene and Heteroaromatics Table 7.15 Wavelength Calculation of the Principal Band of Substituted Benzene Derivatives...
TABLE 7.9 Electronic Absorption Bands for Representative Chromophores... [Pg.708]

Because two-photon selection mles are different from one-photon (electric dipole) selection mles, two-photon transitions may allow access to states which otherwise could not be reached. We shall consider just one example in detail - a two-photon electronic absorption specfrum. [Pg.372]

Electronic Properties. What distinguishes polysdanes from virtually ad. other polymers is their backbone CJ-conjugation. This leads to strong electronic absorption in the near-uv from a O —O transition. For most homo- and copolymers the absorption maximum (/-j ) hes between 300 and 400... [Pg.262]

Polarizability Attraction. AU. matter is composed of electrical charges which move in response to (become electrically polarized in) an external field. This field can be created by the distribution and motion of charges in nearby matter. The Hamaket constant for interaction energy, A, is a measure of this polarizability. As a first approximation it may be computed from the dielectric permittivity, S, and the refractive index, n, of the material (15), where is the frequency of the principal electronic absorption... [Pg.544]

Electronic absorption spectroscopy, UV and visible, has been covered extensively by (63PMH(2)l) and (71PMH(3)67). Table A2 of (B-76MI40402) contains UV absorption data for nearly 70 pyrazoles and pyrazolones. [Pg.197]

Structure of Small and Large Rings Table 7 Electronic Absorption Spectra of Small Heterocyclic Systems... [Pg.13]


See other pages where Electron absorption is mentioned: [Pg.596]    [Pg.584]    [Pg.244]    [Pg.244]    [Pg.1121]    [Pg.1151]    [Pg.1200]    [Pg.117]    [Pg.1143]    [Pg.31]    [Pg.47]    [Pg.43]    [Pg.372]    [Pg.115]    [Pg.118]    [Pg.118]    [Pg.263]    [Pg.11]    [Pg.197]    [Pg.198]    [Pg.318]    [Pg.167]    [Pg.168]    [Pg.168]    [Pg.41]    [Pg.250]    [Pg.14]    [Pg.16]   
See also in sourсe #XX -- [ Pg.15 ]

See also in sourсe #XX -- [ Pg.284 ]




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Ab Initio Calculations of Electronic Absorption Spectra

Absorption core-like electronic states

Absorption hydrated electron

Absorption matrices, electronic

Absorption of electrons

Absorption of solvated electrons

Absorption spectra diatomic electronic

Absorption spectra electron transitions

Absorption spectra electronics

Absorption spectra primary electron donor

Absorption spectroscopy and electron transfer mechanism in proteins

Absorption spectroscopy, lead compounds electronic transitions

Absorption spectrum hydrated electron

Absorption, electron paramagnetic

Absorption, electron paramagnetic resonance

Alkynyl electronic absorption

Anthracene, absorption spectrum electron transfer

Aromatic hydrocarbon absorption electron systems

Biomolecules electronic absorption spectroscopy

Butanal, electronic absorption

Carotenoid cation radical electronic absorption

Case Studies Electronic Absorption Spectrum of Phenyl Radical

Charge-transfer absorption band different electron donors

Charge-transfer absorption band electron acceptor, ionization

Chlorin, electronic absorption

Chlorin, electronic absorption spectra

Chromium electronic absorption spectroscopy

Chromophores, electronic absorption

Chromophores, electronic absorption bands

Cobalt complexes, absorption electronic configuration

Cobalt electron absorption spectroscopy

Complexation electronic absorption spectroscopy

Contents 1 Electronic Absorption Spectrum

Dimeric electronic absorption spectra

Donor electronic absorption spectrum

Electron absorption . linear

Electron absorption band

Electron absorption spectra

Electron absorption spectroscopy

Electron absorption spectroscopy , doped

Electron beam absorption

Electron density absorption

Electron energy absorption

Electron tunneling accompanied by the emission or absorption of light

Electron-transfer dynamics absorption spectroscopy

Electronic (optical) absorption spectroscopy

Electronic Absorption Bands for Representative Chromophores

Electronic Absorption and Emission. Lifetimes. Quenching

Electronic absorption

Electronic absorption

Electronic absorption , square-planar

Electronic absorption band

Electronic absorption band log normal distribution curve, fitted

Electronic absorption bands spectra

Electronic absorption ladder

Electronic absorption of liquid water

Electronic absorption poly

Electronic absorption radical ions

Electronic absorption resonance

Electronic absorption spectra

Electronic absorption spectra bacteriopheophytin

Electronic absorption spectra coordination compounds

Electronic absorption spectra energy

Electronic absorption spectra excitation, collisional

Electronic absorption spectra features

Electronic absorption spectra of octahedral and tetrahedral complexes

Electronic absorption spectra porphyrin, with

Electronic absorption spectra solvent effects

Electronic absorption spectra transition, vibrational structure

Electronic absorption spectra vibronic coupling

Electronic absorption spectra, macrocyclic complexes

Electronic absorption spectra, macrocyclic complexes nickel

Electronic absorption spectral changes

Electronic absorption spectral shifts

Electronic absorption spectrophotometry

Electronic absorption spectroscopy

Electronic absorption spectroscopy (EAS

Electronic absorption spectroscopy bonding parameters

Electronic absorption spectroscopy bonding, excited-state spectroscopic

Electronic absorption spectroscopy case study

Electronic absorption spectroscopy oscillator strength

Electronic absorption spectroscopy physical properties

Electronic absorption spectroscopy probes

Electronic absorption spectroscopy spin allowed transitions

Electronic absorption spectroscopy wave functions

Electronic absorption spectrum isotope effects

Electronic absorption, formula

Electronic effects infrared absorption shift

Electronic spectroscopy absorption spectra

Electronic state, infrared energy absorption

Electronic structure absorption spectroscopy

Electronic transition absorptions

Electronic transitions, ultraviolet-visible absorption spectra

Electrons, light absorption

Excitation, electronic strong coupling, absorption spectra

Free electron absorption

Gaussian curves fitted to electronic absorption ban

Halide electronic absorption spectroscopy

Indoles electronic absorption band

Intervalence electron transfer electronic absorption bands

Light Absorption and Electronically-excited States

Light-matter interactions electronic absorption

MO model, electronic excitation light absorption

Molybdenum complexes electronic absorption spectra

Multiphoton absorption by quasifree electrons

Optical absorption electron, liquid helium

Optical absorption electrons

Perdeuterofulleranes electronic absorption spectra

Phenol electronic absorption spectrum

Phenyl radical electronic absorption spectrum

Pheophytin, electronic absorption

Photoelectron and Electron Absorption Spectra of Cyclic 1,3-Diynes

Photoinduced absorption-detected electron

Phthalocyanine electronic absorption spectra

Phthalocyanines electronic absorption spectra

Plasma Absorption and Reflection of Electromagnetic Waves Bouguer Law Critical Electron Density

Polyyne electronic absorption spectra

Pump-probe electronic absorption spectroscopy

Quantum dots electron absorption spectroscopy

Radical anions electronic absorption spectra

Radicals electronic absorption

Reaction electronic absorption

Room temperature electronic absorption

Room temperature electronic absorption spectrum

Rose bengal electronic absorption

Solvated electron absorption spectrum

Solvated electron optical absorption

Solvent effects on electronic absorption spectra

Speciation of Niobium in Chloride Melts An Electronic Absorption Spectroscopic Study

Spectra, electronic absorption optical

Spectra, electronic absorption solution

Spectral electronic absorption

Spectrometry electronic absorption

Studies of Cyclodextrin Inclusion Complexes by Electronic (UV-Vis Absorption and Emission) Spectroscopy

Time-resolved electronic absorption

Time-resolved electronic absorption spectroscopy, limitations

Transition element complexes electronic absorption spectra

Transmission electron microscopy UV-vis absorption spectrum

Trapped electron optical absorption band

Water electronic absorption

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