Valence-state ionisation potential

The same relationship is plotted in Fig. 32 in a way which is more customary than Fig. 24 for a discussion of reactions at electrodes. The reduction potential of the excited singlet state of rhodamine ° id /2d- has been fixed according to Fig. 31 relative to the valence bands (ionisation energies) at the surface of the organic crystals. The distribution curve for the empty and occupied excited singlet state of rhodamine is also drawn according to Fig. 31. A comparison with the above estimated value of... 

The decay of the valence state of the bare TDMAE molecule has been analysed in a cold supersonic beam after excitation at 266 nm, in a former work[6]. The ionisation potential of TDMAE is sufficiently low that excitation of the valence state at 266 nm allows probing the V state at 800 nm with an excess energy of 0.8 eV. The monotonic decay of the V state was observed with a 300 fs time constant. This decay is accompanied by the simultaneaous rise of the Z state detected with two 800 nm photons. This latter state further decays in 100 ps. This results in a bi-exponential signal for the TDMAE+ ions. 

Using the definitions of the orbital electronegativity presented in eqs. (3.5, 4.10 and 4.11) together with the latest experimental values for the ionisation potentials, electron affinities and term values for the atoms, an extensive reevaluation of the atomic valence state promotion energies and electronegativities has been carried out[28-30]. The results obtained are presented in Chart 1 and in more detail in Table 1. 

As Mulliken pointed out, the ionisation potential and electron affinity are specific to a given valence state of an atom, and therefore the electronegativities of an atom s valence states would not be expected to be the same. This idea can be extended to the concept of orbital... 

Fig. 32. The relationship between the reduction potential 0TTiI) /D- of the excited singlet state of rhodamine and the ionisation energies Ic at the surface of the organic crystals as derived from the yield for hole generation at the different crystals (Fig. 31). As an example at anthracene the potential curve (valence band) is shown for the hole moving into the crystal bulk at two different external field strengths 3 x 105 V/cm (solid curve) and 1 X 105 V/cm (dashed curve)...

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