# Ultrafast dynamics of photoinduced charge separation

## TL;DR

This review discusses recent advances in understanding ultrafast photoinduced charge separation, emphasizing experimental and theoretical insights into mechanisms involving quantum coherence and electron-nuclear interactions in nanoscale systems.

## Contribution

It provides a comprehensive overview of the latest experimental observations and theoretical models explaining ultrafast charge separation in molecular and nano-sized systems.

## Key findings

- Quantum coherence influences charge separation dynamics.
- Electron-nuclear coupling plays a key role in ultrafast processes.
- Theoretical models align with experimental ultrafast observations.

## Abstract

Phenomena involving electron transfer are ubiquitous in nature, photosynthesis and enzymes or protein activity being prominent examples. Their deep understanding thus represents a mandatory scientific goal. Moreover, controlling the separation of photogenerated charges is a crucial prerequisite in many applicative contexts, including quantum electronics, photo-electrochemical water splitting, photocatalytic dye degradation, and energy conversion. In particular, photoinduced charge separation is the pivotal step driving the storage of sun light into electrical or chemical energy. If properly mastered, these processes may also allow us to achieve a better command of information storage at the nanoscale, as required for the development of molecular electronics, optical switching, or quantum technologies, amongst others. In this Topical review we survey recent progress in the understanding of ultrafast charge separation from photoexcited states. We report the state-of-the-art of the observation and theoretical description of charge separation phenomena in the ultrafast regime mainly focusing on molecular- and nano-sized solar energy conversion systems. In particular, we examine different proposed mechanisms driving ultrafast charge dynamics, with particular regard to the role of quantum coherence and electron-nuclear coupling, and link experimental observations to theoretical approaches based either on model Hamiltonians or on first principles simulations.