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Transition atomic

The wavelengths associated with the 2Py2 2P% transitions of the halogen atoms are given in Table III. In the types of controlled experiments to be [Pg.6]

Optical Transitions of the Halogen Atoms observed by Absorption Spectroscopy in the Vacuum Ultraviolet [Pg.8]


In equations (Cl. 4.4) and (Cl. 4.5) Acoj = cu - coj is the detuning of the optical field from the atomic transition frequency Q is the natural width of the atomic transition and m is tenned the Rabi frequency and reflects the... [Pg.2458]

Altliough an MOT functions as a versatile and robust reaction cell for studying cold collisions, light frequencies must tune close to atomic transitions and an appreciable steady-state fraction of tire atoms remain excited. Excited-state trap-loss collisions and photon-induced repulsion limit achievable densities. [Pg.2471]

Markov modeling is a technique for calculating system reliability as exponential transitions between various states of operability, much like atomic transitions. In addition to the use of constant transition rates, the model depends only on the initial and final states (no memory). [Pg.48]

Fig. 6. Optical spectrum of Ir atoms isolated in solid Ar at 10-12 K, compared to the gas-phase atomic transitions of Ir. The stick heights correspond to reported oscillator strengths of gaseous Ir atoms (49). Fig. 6. Optical spectrum of Ir atoms isolated in solid Ar at 10-12 K, compared to the gas-phase atomic transitions of Ir. The stick heights correspond to reported oscillator strengths of gaseous Ir atoms (49).
Techniques other than UV-visible spectroscopy have been used in matrix-isolation studies of Ag see, for example, some early ESR studies by Kasai and McLeod 56). The fluorescence spectra of Ag atoms isolated in noble-gas matrices have been recorded (76,147), and found to show large Stokes shifts when optically excited via a Si j — atomic transition which is threefold split in the matrix by spin-orbit and vibronic interactions. The large Stokes shifts may be explained in terms of an excited state silver atom-matrix cage complex in this... [Pg.95]

Fig. 6. The low-lying level structure of "Tc and the relevant atomic transition close to the isomeric transition in energy (keV) [25]... Fig. 6. The low-lying level structure of "Tc and the relevant atomic transition close to the isomeric transition in energy (keV) [25]...
Atomic metal ion-hydrocarbon reactions bond dissociation energies for fragments, 15,16t endothermic reactions, 13,15,17f Atomic transition metal ion reactions development of approach for real-time measurements of dissociation kinetics, 39 ion beam apparatus, 12,14f studies of... [Pg.331]

The idea of a transition between two energy levels suggests that the transition will occur at only one precise frequency as a sharp spike in the absorption or emission spectrum. This is not the case and, in fact, the transitions have an intrinsic width and shape containing information about the local environment of the atoms. The line profile of an atomic transition has contributions from three effects ... [Pg.46]

Calculate the Doppler shift that should be observed in the hydrogen atom transition at 656.300 nm for the ascending and descending limbs of Jupiter at the equator. [Pg.51]

The rate of this intramolecular isomerization depends on the chain length, with the maximum in the case of a six-atomic transition state, i.e., when the tertiary C—H bond is in the (3-position with respect to the peroxyl group [13]. For the values of rate constants of intramolecular attack on the tertiary and secondary C—H bond, see Table 2.9. The parameters of peroxyl radical reactivity in reactions of intra- and intermolecular hydrogen atom abstraction are compared and discussed in Chapter 6. [Pg.78]

Atoms, ions and molecules present in the stars provide additional opacity at wavelengths corresponding to specific atomic transitions these give rise to comparatively narrow absorption lines (see Fig. 3.2) with intensities related to the abundances of the relevant elements (and much else). Despite the name, processes other than pure absorption (e.g. scattering and fluorescence) are involved in the production of these lines and, while they are often treated in LTE, this is now only a simplifying approximation which often works fairly well, but needs to be checked by more detailed calculations for each particular case. (In some cases, there are even emission lines or emission components, e.g. the solar Ca+ H and K lines in the near UV, which are so strong that the chromosphere affects their central parts.)... [Pg.55]

W. L. Wiese, J. R. Fuhr and T. M. Dieters, Atomic Transition Probabilities for Carbon, Nitrogen and Oxygen A Critical Data Compilation, J. Phys. Chem. Ref. Data, Monograph 7, 1996. [Pg.114]

In a celebrated paper, Einstein (1917) analyzed the nature of atomic transitions in a radiation field and pointed out that, in order to satisfy the conditions of thermal equilibrium, one has to have not only a spontaneous transition probability per unit time A2i from an excited state 2 to a lower state 1 and an absorption probability BUJV from 1 to 2 , but also a stimulated emission probability B2iJv from state 2 to 1 . The latter can be more usefully thought of as negative absorption, which becomes dominant in masers and lasers.1 Relations between the coefficients are found by considering detailed balancing in thermal equilibrium... [Pg.407]

Photomultipliers are generally used to convert the spectral radiation to an electrical current and often phase-sensitive lock-in amplifiers are used to amplify the resulting current. AES and AFS require similar read-out systems because both methods are measuring small signals. The difficulty associated with both these methods is the separation of the signal for the atomic transition of interest from the background radiation emitted by excited molecular species produced in the atom reservoir. AFS phase locks the amplifier detection circuit to the modulation frequency of the spectral source. Modulation of the source is also used in AAS. [Pg.244]

Being related to a resonant behavior of the opacity for the extraordinary mode, the proton cyclotron line appears as an absorption feature in the spectrum. Atmospheres comprised of heavy elements (Fe) were studied by Rajagopal et al. (1997) the emergent spectra exhibit a variety of emission/absorption features produced by atomic transitions. Such models, however, suffer from our lack of knowledge of the ionization states and opacities of metals in a strong magnetic field. [Pg.63]

EXO 0748-676, Cottam et al. (2002) have found absorption spectral line features, which they identify as signatures of Fe XXVI (25-time ionized hydrogenlike Fe) and Fe XXV from the n = 2 —> 3 atomic transition, and of O VIII (n = 1 —> 2 transition). All of these lines are redshifted, with a unique value of the redshift z = 0.35. Interpreting the measured redshift as due to the strong gravitational field at the surface of the compact star (thus neglecting general relativistic effects due to stellar rotation on the spectral lines (Oezel Psaltis 2003)), one obtains a relation for the stellar mass-to-radius ratio ... [Pg.370]

The second source for which it has been claimed the detection of redshifted spectral lines is IE 1207.4-5209, a radio-quite compact star located in the center of the supernova remnant PSK 1209-51/52. IE 1207.4-5209 has been observed by the Chandra X-ray observatory. Two absorption features have been detected in the source spectrum and have been interpreted (Sanwal et al. 2002) as spectral lines associated with atomic transitions of once-ionized helium in the atmosphere of a strong magnetized (B 1.5 x 1014 G) compact star. This interpretation gives for the gravitational redshift at the star surface z = 0.12 -0.23 (Sanwal et al. 2002), which is reported in Fig. 3 and by the two dashed lines labeled z = 0.12 and z = 0.23. [Pg.371]

As already noted, in the Born-Oppenheimer approximation, the nuclear motion of the system is subject to a potential which expresses the isotope independent electronic energy as a function of the distortion of the coordinates from the position of the transition state. An analysis of the motions of the N-atom transition state leads to three translations, three rotations (two for a linear molecule), and 3N - 6 (3N- 5 for a linear transition state) vibrations, one which is an imaginary frequency (e.g. v = 400icm 1 where i = V—T), and the others are real vibrational frequencies. The imaginary frequency corresponds to motion along the so-called reaction... [Pg.120]


See other pages where Transition atomic is mentioned: [Pg.2457]    [Pg.2458]    [Pg.2467]    [Pg.398]    [Pg.319]    [Pg.248]    [Pg.122]    [Pg.311]    [Pg.343]    [Pg.161]    [Pg.751]    [Pg.212]    [Pg.354]    [Pg.751]    [Pg.535]    [Pg.15]    [Pg.16]    [Pg.16]    [Pg.17]    [Pg.24]    [Pg.42]    [Pg.14]    [Pg.14]    [Pg.103]    [Pg.244]    [Pg.132]    [Pg.246]    [Pg.368]    [Pg.120]   
See also in sourсe #XX -- [ Pg.13 ]




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A Note on Heavy Atoms and Transition Metals

Activation by Second-Row Transition-Metal Atoms

Amide oxides reactions with transition metal atoms

Approximate Atomic Transition Amplitudes

Atom transfer radical addition transition metal catalyzed

Atom transition, optical

Atom, electronic transitions

Atomic Adsorption on a Transition or d Metal

Atomic Radii and the Transition Elements

Atomic and Physical Properties of the Transition Elements

Atomic electronic transitions

Atomic electronic transitions assignment

Atomic force microscopy phase transition

Atomic natural orbitals transition metal systems

Atomic orbitals, transition elements

Atomic properties transition elements

Atomic radii among transition metals

Atomic radii of transition metals

Atomic radius transition elements

Atomic radius within transition series

Atomic size transition elements

Atomic spectra transition probabilities

Atomic spectra, transition metal

Atomic spectra, transition metal clusters

Atomic spectra, transitions

Atomic spectroscopy energy transitions

Atomic structure transitions

Atomic systems inverted transitions

Atomic transition metal ion

Atomic transition probability

Atoms transition probabilities

Clock atomic transition

Closed-shell transition metal atom states

Clusters with more than four transition-metal atoms

Clusters with seven or more transition-metal atoms

Clusters, transition metal with interstitial atoms

Coherent states atomic transitions

Decaying atomic transitions, quantum

Dressed-atom model dark transition amplification

Effect of Heavy Atoms on Intercombinational Transitions in Aromatic Compounds

Electron affinity transition metal atoms

Electronic transitions in an atom

Electronic transitions in atoms

Electronically excited halogen atoms atomic transitions

Elements atomic transition probability

Equivalent atomic number , transition

Excitation transition metal atoms

FORBIDDEN TRANSITIONS AND METASTABLE ATOMS

Fluorescence spectrum decaying atomic transitions

Forbidden atomic transitions

Formation of Exopolyhedral a Bonds between Cage Boron Atoms and Transition Elements

Four-atom concerted transition state

Free transition metal atoms

Gaseous transition metal atoms

Hartree-Fock approximation transition metal atoms

Heavy Atoms and Transition Metals

Helium atom phase transition

Hydrogen bonds involving transition metal atoms

Intra-atomic transitions

Metal atoms transition elements

Metastable atoms forbidden transitions

Molecular systems, quantum interference atomic transitions

Molecular-atomic transition

NIST Atomic Transition Probability Tables

Net Charges of Transition Metal Atoms

Observable transitions in atoms and molecules

Oxidative Degradation of 1 C Atom (Hexose-pentose Transition)

Oxygen atom transfer transition structures

Phase transitions three-electron atoms

Phase-space transition states atomic clusters

Quadruple Bonds between Transition Metal Atoms

Quantum interference atomic transitions

Radiationless transitions heavy-atom effect

Recoil Energy Loss in Free Atoms and Thermal Broadening of Transition Lines

Singlet-triplet transitions external heavy atom effect

Species containing interstitial transition-metal atoms

Sulfur atoms, electronic states transition state

The External Heavy Atom Effect on S-T Transitions

The Nonmetal Atom Sharing Rule of Low-Barrier Transition States

Transition Elements Atomic Structure and Properties

Transition Metal Atoms on MgO

Transition Metal Silylenoid-Catalyzed Atom Transfer Reactions

Transition atomic energies

Transition elements metal atom clusters

Transition elements physical and atomic

Transition from (A, S) to (Ji,J2) coupling for the 2P 2S separated atom states

Transition metal atom

Transition metal atomic size

Transition metal atoms formal oxidation states

Transition metal atoms reactions with organic substrates

Transition metal catalysts atom/group-transfer reactions

Transition metal clusters, boron atoms

Transition metal clusters, boron atoms geometry

Transition metal clusters, boron atoms structure

Transition metal clusters—continued atoms

Transition metal local atomic structure

Transition metals atomic carbon adsorption

Transition metals atomic radii

Transition metals interstitial atoms

Transition probability of atoms

Transition state for hydrogen atom abstraction

Transition, radiative atomic, inner shell

Transition-metal atoms, molecular

Transition-metal atoms, molecular systems

Triosmium Clusters with Introduced Transition Metal Atoms

Why Do Hydration Heats of Transition-Metal Ions Vary Irregularly with Atomic Number

X-rays transitions in the molybdenum atom

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