Excited states transformations

Organic Dyes with Excited-State Transformations (Electron,... 

Fig. 5 General scheme of ground-state and excited-state transformations and emissions in the case of a reversible excited-state reaction involving one of the two ground-state species (from Ref. [62], modified)...

Hsieh CC, Ho ML, Chou PT (2010) Organic dyes with excited-state transformations (electron, charge and proton transfers), A.P. Demchenko (ed.), Advanced Fluorescence Reporters in Chemistry and Biology I, Springer Ser Fluoresc 8 225-266... 

Once the state symmetries have been established it only remains to be shown that the direct product of the species of the ground state symmetry, the coordinate translational symmetries and the excited state symmetry belong to the totally symmetric species A. Let us take the n-wr transition in formaldehyde. The ground state total wave function has the symmetry Ax. The coordinate vectors x, y and z transform as By, Bf and Ax respectively (refer Character Table for C2k Section 2.9, Table 2.2), The excited state transforms as symmetry species A2. The direct products are ... 

Table 6-1. C h molecular point group. The electronic states of the flat Tg molecule are classified according to the two-fold screw axis (C2), inversion (z), and glide plane reflection (ct/,) symmetry operations. The and excited states transform like translations (7) along the molecular axes and are optically allowed. The Ag and It, states are isomorphous with the polarizability tensor components (a), being therefore one-photon forbidden and two-photon allowed.

The function corresponding to the first excited state transforms according to the irreducible representation P, to which the normal mode 1 belongs. Thus, transforms according to r X Ai X Ai X Ai X Ai = T i.e., it belongs to the same irreducible representation as i... 

The sum over the X components of the excited state, transforming as the A irrep, can be simplified by using the orthonormality property of the coupling coefficients fromEq. (6.16). 

Quendiii of Exdted States.—Much research has been adapted from early observations that micelles could drastically alter the fluorescence lifetime of pyrene and the efficiency of excimer formation. The various mechanisms of excited-state transformation have been reviewed. " The polarity of the micellar surface may be estimated from the fluorescence spectrum of pyrene 2-carboxaldehyde " giving rise to the conclusion that sodium laurylsulphate (e=45) has a more polar surface than cetyltrimethylammonium bromide (e = 18). The fluidity of the site of solubilization may be estimated from fluorescence polarization " in surfactants of general structure (104). The Si... 

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