Oscillator strength parameters

The values of 5edimeas) calculated from equation (2) can be substituted into formula (3) to determine the oscillator strength parameter Q2,04 and Qe-... 

We now want to study the consequences of such a model with respect to the optical properties of a composite medium. For such a purpose, we will consider the phenomenological Lorentz-Drude model, based on the classical dispersion theory, in order to describe qualitatively the various components [20]. Therefore, a Drude term defined by the plasma frequency and scattering rate, will describe the optical response of the bulk metal or will define the intrinsic metallic properties (i.e., Zm((a) in Eq.(6)) of the small particles, while a harmonic Lorentz oscillator, defined by the resonance frequency, the damping and the mode strength parameters, will describe the insulating host (i.e., /((0) in Eq.(6)). 

CEX (ionization potential) = 13.6 eV, Yn = 6.08 eV f°r N atom of indoline ring is used in PPP calculation. The carbon for indoline component is ignored for PPP calculation. Other parameters listed in Ref. 15. Oscillator strength. 

The parameter e0 was chosen for best agreement with the experimental data of Opal et al.52 at = 500 eV. Jain and Khare applied this equation to the calculation of ionization cross sections for C02, CO, HzO, CH4, and NH3 and achieved fairly good agreement with experiment for all cases except for CO, where the cross section was too low, though the ionization efficiency curve still exhibited the correct shape. The main limitation of this method, which it has in common with the BED theory, is the inclusion of the differential oscillator strengths for the target molecule which restricts the number of systems to which it can be applied. 

The Na I D-lines have wavelengths and oscillator strengths A,i = 5896 A, /i = 1 /3, and X2 = 5889 A, f2 — 2/3. In a certain interstellar cloud, their equivalent widths are measured to be 230 mA and 370 mA respectively, with a maximum error of 30 mA in each case. Assuming a single cloud with a Gaussian velocity dispersion, use the exponential curve of growth to find preferred values of Na I column density and b, and approximate error limits for each of these two parameters. (Doublet ratio method.)... 

Of course these generalizations must be used with caution however, they are useful in comparing similar compounds. For a series of octahedral Cr(III) complexes it has been found that the oscillator strength, /, varies approximately linearly with the nephelauxetic parameter, j3, also a measure of covalency. ... 

A2g transitions, respectively. Besides being able to correlate jS with oscillator strength,/, of transitions the values may be employed 42) to evaluate the effective charges on the Cr(III) ions in various complexes. Fig. 4 provides plots of the effective metal charge vs. /3, the nephelauxetic parameter and B, the Racah interelectronic repulsion parameter for chromium(III). Jorgensen... 

The dipole strength is a measure of the intensity of the transition to state J in the absorption spectrum and is closely related to the oscillator strength. The MCD intensity and thus MCD parameters produced by a particular transition are proportional to the absorption intensity of that transition. 

The main advantage of the effective potential method consists in the relative simplicity of the calculations, conditioned by the comparatively small number of semi-empirical parameters, as well as the analytical form of the potential and wave functions such methods usually ensure fairly high accuracy of the calculated values of the energy levels and oscillator strengths. However, these methods, as a rule, can be successfully applied only for one- and two-valent atoms and ions. Therefore, the semi-empirical approach of least squares fitting is much more universal and powerful than model potential methods it combines naturally and easily the accounting for relativistic and correlation effects. 

Line and multiplet strengths are useful theoretical characteristics of electronic transitions, because they are symmetric, additive and do not depend on the energy parameters. However, they are far from the experimentally measured quantities. In this respect it is much more convenient to utilize the concepts of oscillator strengths and transition probabilities, already directly connected with the quantities measured experimentally (e.g. line intensities). Oscillator strength fk of electric or magnetic electronic transition aJ — a J of multipolarity k is defined as follows ... 

Let us also notice that slow variations of K with Z imply that the gauge condition K may be treated as a semi-empirical parameter in practical calculations to reproduce, with a chosen K, the accurate oscillator strength values for the whole isoelectronic sequence. Thus, dependence of transition quantities on K may serve as the criterion of the accuracy of wave functions used instead of the comparison of two forms of 1-transition operators. In particular, the relative quantities of the coefficients of the equation fEi = aK2 + bK +c (the smaller the a value, the more exact the result), the position of the minimum of the parabola Kf = 0 (the larger the K value for which / = 0, the more exact is the approximation used, in the ideal case / = 0 for K = +oo) may also help to estimate the accuracy of the method utilized. 

Taking advantage of advances in computational atomic and plasma physics and of the availability of powerful supercomputers, a collaborative effort - the international Opacity Project - has been made to compute accurate atomic data required for opacity calculations. The work includes computation of energy levels, oscillator strengths, photoionization cross-sections and parameters for pressure broadening of spectral lines. Several... 

A medium with bound electrons can be regarded as an ensemble of oscillators each of which is characterized by three parameters its natural frequency oscillator strength/, and the damping constant y(, which equals the inversed lifetime of the corresponding state ("y, = 1 /r,). The well-known expression for the permittivity of the medium91,95 can be presented in the form89... 

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