Femtosecond liquid dynamics studied by two-dimensional Raman spectroscopy

摘要: Lacking the symmetric order of solids or isolation gases, liquids are intrinsically more complicated than other states matter due to inherent randomness and subtle interplay various many-body interactions. In understanding dynamics in chemical processes, it is sensible look first at pure liquids. The timescales, on which interesting phenomena occur, span many orders magnitude, but basic interactions fundamentally determined by vibrational periods, these generally sub-picosecond. Liquids motions characterized frequencies that smaller typical intramolecular bond vibrations, range from 10-500 cm -1 . Though tremendous recent progress has been made study their couplings even hydrogen bonded systems, approaches yield only a local picture liquid. To build solvent, one needs focus larger scale involving solvent molecules, direct attention towards collective dynamics. However, this conceptually challenging prospect places significant demands state art both theoretical descriptions experimental techniques.