Evolution from sub-picosecond nonequilibrium nuclear dynamics to nanosecond ground-state kinetics

Ascertain the detailed evolution pathways by which excited chemical and biomolecular systems transition from nonequilibrium nuclear dynamics on sub-picosecond timescales to nanosecond-scale ground-state kinetics via microcanonical energy distribution mechanisms, including the temporal and mechanistic characteristics of this transition.

Background

The paper proposes simultaneous real- and momentum-space electron diffraction measurements for C60 and suggests that tuning electron impact energy could serve as a knob to control pump–probe delays in ultrafast electron diffraction experiments. This capability is relevant to resolving dynamics that span picosecond to nanosecond timescales.

Within this broader context, the authors point out that for many chemical and biomolecular processes the specific manner in which systems evolve from a nonequilibrium nuclear state shortly after excitation to slower ground-state kinetics remains poorly characterized. They highlight this gap to motivate future ultrafast studies that leverage controllable electron speeds and combined angle–momentum diffractograms to probe such transitions.