Contents of Research

Contents of Research 

Control of molecular motion and reaction dynamics by photoirradiation, electric field and magnetic field

Control of molecular motion and reaction dynamics by photoirradiation, electric field and magnetic field

1) Spectral Shift and spread of spectrum can be observed when an electric field is applied

A level shifts in accordance with the magnitude of electric dipole moment (deviation of electron cloud) and polarizability (spread of electron cloud) of each state to generate the Stark shift. In a randomly distributed system, as shown in Fig. 1, the amount of change in polarizability can be estimated from the spectral shift (the first derivative of the spectrum). The amount of change in electric dipole moment can be estimated from the spread of spectrum (secondary derivation).

2) Polar molecules can cause molecular orientation when an electric field is applied

Changes in absorption intensity in a polarization experiment reveal molecular orientation. At the Magic angle shown in Fig. 2, there is no change in intensity that is in molecular orientation.

3) Dynamics of excitation state changes when an electric field is applied

In an electron transfer reaction, a product (radical ion pair) has large electric dipole moment. As shown in Fig. 3 below, a level shifts by an electric field, a difference in free energy of a reaction changes, and changes in mobility of electrons can be expected. In that case, it is possible to estimate the amount of changes by estimating the electric field induced changes in radiation intensity and by the effect of an electric field on emission decay.

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