Short timescale regime motion

There are two interesting regimes of time evolution in the probing/detection of dynamical nonequilibrium structures. In the regime of dynamics, the time evolution of atomic positions is detected on its intrinsic timescale, i.e., femtoseconds. Short X-ray pulses - on the timescale of atomic motion - are required in order to follow the dynamics of the chemical bond. In the regime of kinetics, which has to do with the time evolution of populations - and in the context of time-resolved X-ray diffraction -the time evolution in an ensemble average of different interatomic distances or the structural determination of short-lived chemical species is considered. 

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