This lowest energy transitions are dominated by ligand-to-ligand charge transfer (LLCT) with some admixture of metal-to-ligand charge transfer (MLCT) and exhibit much smaller

oscillator strength as compared to the main band.

Main excitation energy [wavelength (nm) and calculated energy (eV)], oscillator strength (f), and iheir main corresponding configuration of PFBT (H; HOMO: L: LUMO: L+1; LUMO+1.

1] is dominated by HOMO [right arrow] LUMO excitation with an oscillator strength (f) of about 1.

Main excitation energy [wavdength (nm) and calculated energy (cV)], oscillator strength (f) and their corresponding configuration of PFBT and PCzBT (H.

The second blue absorption band is identified with a delocalized excitonic [pi]--[pi] * transition at higher energy, corresponding to the [pi]-conjugated segments of the polymer backbone, which are characterized by much smaller oscillator strength.

Let the absolute value of the

oscillator strength at yield be [F.

It is more convenient to express of the differential cross section in terms of a quantity known as the Generalized

Oscillator Strength, F (q, [epsilon]) defined by

Similarly, the quadratic Stark effect can be calculated from a knowledge of the electric-dipole oscillator strengths.

Equations (16) and (17) can be rewritten in terms of the oscillator strengths [f.

scalar] (S, 1/2), the oscillator strengths for all electric-dipole transitions connecting the [5d.

Wilson, Atomic Spectra and Oscillator Strengths for Astrophysics and Fusion Research, J.