Oscillator strength energy moment

Calculated and Experimental Excitation Energies, Oscillator Strengths, Dipole Moments (/ ,), and Transition Moment Directions for the ir— ir Excited Valence Singlet States in Indole... 

The strength or intensity of absorption is related to the dipole strength of transition D or square of the transition moment integral M m , and is pressed in terms of oscillator strength / or integrated molar extinction jfe Jv. A transition with /= 1, is known as totally allowed transition. But the transitions between all the electronic, vibrational or rotational states are not equally permitted. Some are forbidden which can become allowed under certain conditions and then appear as weak absorption bands. The rules which govern such transitions are known as selection rules. For atomic energy levels, these selection rules have been empirically obtained from a comparison between the number of lines theoretically... 

The Ta <— So transition moments to particular spin sublevels for the three lowest triplet states of the ozone molecule, 3B2,3 A2 and 3B, were calculated by the MCQR method in ref. [70] using CASSCF wave functions. Table 7 recapitulates results for electric dipole radiative activity of different S-T transitions in ozone [70]. The type of information gained form this kind of spin-orbit response calculations are viz. transition electric dipole moments and oscillator strengths for each spin sublevel T , their polarization directions (7), radiative lifetimes (r ) and excitation energies (En). The most prominent features of the Chappuis band are reproduced in calculations, which simulate the photodynamics of ozone visible absorption [78, 79]. Because the CM (M2) state cannot be responsible for the Wulf bands, the only other candidates ought to... 

Table 7 Calculated S-T transition moments from the ground state (So) to the three lowest triplet states (Tn) at the ground state geometry, oscillator strengths (/), radiative lifetimes (rn), and vertical transition energy (En). From Ref. [70].

Table 14-1. Computed and experimental transition energies (AE eV), dipole moments (p Debye), oscillator strengths (f) and transition moment directions (d> °) according to Tinoco-DeVoe convention of hypoxanthine [159]... 

Table 38 Calculated excitation energies (in eV), oscillator strength, and transition dipole moment (in D) for the coumarin derivative Cl in different media. Two different polarizable-continuum models (SCRF-S and PCM) and four different density functionals (CAMB3LYP, mCAMB3LYP, PBEO, and B3LYP) have been used. In all cases, the same size of the basis set has been used, except for the B3LYP calculations in vacuum, for which the second and third entry list results for a smaller and a larger basis set, respectively. All results are from ref. 92 ...

Note that the thresholds can easily be measured by electron impact, while this is not possible for Hg, n > 2 at the moment by photoionisation owing to the very small oscillator strength at threshold." The electron energy scale was calibrated by the well known ionisation potentials of atomic Hg and Ar. The difference between the two thresholds is reproducible to 0.05 eV. The error in the ionisation potentials (Ej) is difficult to estimate. The overall accuracy is +100 meV at n = 13 and 300 meV at n = 90. However, the point-to-point variation of the data, i.e. the difference in error between Ei(n) and ,(n -I- 1) is much less, and is expected to be [Pg.26]

In equation 12, W is the energy of the optical transition, /is the oscillator strength, and g is the difference between ground-state and excited-state dipole moments. Increases in the electron-donating ability of the donor substituent and the electronegativity of the acceptor should increase both A Xg g and/to a point that should have a favorable impact on p. Beyond that point, further increases in polarity will result in decreases in both F and A Xgg, and P will become smaller. 

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