The Mapping Approach to Surface Hopping (MASH) method, developed in the group, has emerged as an alternative to the fewest-switches surface hopping (FSSH) method. In this work, we assess the accuracy of the MASH method in electronic coherences prediction. These quantities are key to the study of Conical Intersections through novel X-ray spectroscopies, such as the transient redistribution of ultrafast electronic coherences in attosecond Raman signals (TRUECARS).

Instanton theory reveals a crossover between a sequential and a concerted tunelling mechanism.

MASH is now reversible!