Picosecond Flash Photolysis and Spectroscopy:Bis-(4-Dimethylaminodithiobenzel)-Ni(II), (BDN).

摘要

The transient absorption spectrum of an electronically excited dithiene,bis-(4-dimethylaminodithiobenzil)-Ni(II), BDN,was measured with 10ps temporal resolution and 1nm wavelength resolution. For a series of 'heavy atom'solvents,both the ground state and the excited state spectra remained constant while the decay kinetics of the excited state absorption,as well as the recovery from ground state bleaching,varied. The excited state spectrum can plausibly be fit by a particular one electron transition between previously calculated molecular orbitals,although this clearly does not prove that these orbitals provide the best description for the excited states. The authors comment on three possibilities within the framework of the ground state virtual orbital picture. The recently developed techniques will be generally applicable in probing the photodynamics of presently intractable molecular species. The significance of the data for laser mode-locking is discussed. (Modified author abstract)