Illumination guidelines for ultrafast pump-probe experiments by serial femtosecond crystallography.

Grünbein, Marie Luise; Stricker, Miriam; Nass Kovacs, Gabriela; Kloos, Marco; Doak, R Bruce; Shoeman, Robert L; Reinstein, Jochen; Lecler, Sylvain et al. · Nat Methods · 2020

basic_science · Level V

Where this comes from

Abstract

Time-resolved crystallography with X-ray free-electron lasers enables structural characterization of light-induced reactions on ultrafast timescales. To be biologically and chemically relevant, such studies must be carried out in an appropriate photoexcitation regime to avoid multiphoton artifacts, a common issue in recent studies. We describe numerical and experimental approaches to determine how many photons are needed for single-photon excitation in microcrystals, taking into account losses by scattering.

Medical subject headings