Two decades of imaging photoelectron circular dichroism: from first principles to future perspectives

There has been a significant recent surge in the number of studies interrogating chiral molecules in the gas phase using photoelectron circular dichroism (PECD) and related techniques. These investigations have revealed new fundamental insights into the structure and dynamics of chiral species and, furthermore, have the potential to revolutionize the field of chiral analysis for more practical and industrial applications. As it has been just over 20 years since the first PECD imaging experiments were demonstrated - and 10 years since the last dedicated general perspective article on the topic - a new overview now seems extremely timely. This article will introduce PECD to the general reader and give a synopsis of developments in the field, focusing particularly on the last decade, where the use of multiphoton ionization schemes has brought PECD to a wider experimental audience. We will discuss the novel applications of the general methodology and highlight the challenges that must be overcome to fully cement PECD and adjacent techniques as powerful chiral analysis probes.