Laue diffraction and time-resolved crystallography: a personal history

Abstract

A personal, historical view is presented of Laue X-ray diffraction and its application to time-resolved studies of dynamic processes, largely in light-sensitive biological systems. In Laue diffraction, a stationary crystal is illuminated by a polychromatic X-ray source. Laue diffraction has inherent complications largely absent in monochromatic diffraction, and consequently fell into disuse for quantitative structure determination. However, the advent of naturally polychromatic, intense, pulsed storage ring X-ray sources in the 1970s led to re-examination at Daresbury and elsewhere of its underlying principles. Laue diffraction has been successfully applied at storage ring sources to time-resolved, pump–probe crystallographic studies, whose exposure time and time resolution were progressively reduced from minutes to seconds, milliseconds, nanoseconds and 100 ps. Most recently, hard X-ray free electron laser sources have been used to generate narrow bandpass Laue diffraction patterns. The femtosecond X-ray pulses from such sources are completely destructive, generate only one diffraction pattern per tiny crystal and have unusual properties. However, they too are being applied to time-resolved crystallography to explore, for example, isomerization and rapid tertiary structural changes on the chemical, femtosecond timescale. This article is part of the theme issue ‘Fifty years of synchrotron science: achievements and opportunities’.

Systems Approach of Photoisomerization Metrology for Single-Crystal Optical Actuators: A Case Study of [Ru(SO2)(NH3)4Cl]Cl

“…Photoisomerization is an archetypal mechanism to afford light-induced structural changes. , Its occurrence within single crystals has been evidenced by a range of pioneering experimental developments, especially those involving light-induced in situ single-crystal X-ray diffraction. − “Seeing is believing” when it comes to a crystal structure, which is generally regarded as the ’gold standard’ of materials characterization. A range of steady-state − and time-resolved experiments ,, have contributed significantly to the technical development of light-induced in situ single-crystal X-ray diffraction. This subject has evolved to become known as “photocrystallography”.…”

“…8−12 "Seeing is believing" when it comes to a crystal structure, which is generally regarded as the 'gold standard' of materials characterization. A range of steady-state 8−12 and time-resolved experiments 9,13,14 have contributed significantly to the technical development of light-induced in situ single-crystal X-ray diffraction. This subject has evolved to become known as "photocrystallography".…”

Spatiotemporal mapping of microscopic strains and defects to reveal Li-dendrite-induced failure in all-solid-state batteries

“…The spatial resolution was brought down to the sub-100-nm level in 2016 [65]. With the development of hard X-ray free electron lasers, the spatial and temporal resolution of the Laue diffraction technique is expected to be further improved [66] and more dynamic study will be enabled.…”

Using photocaging for fast time-resolved structural biology studies

“…Time-resolved structural biology has been possible for decades. The use of pump-probe Laue crystallography to achieve submillisecond time resolutions was first demonstrated in the 1990s (Moffat, 2019). In such experiments, the reaction of interest is triggered in an ensemble of biomacromolecules (usually with light), and the structure is probed after a pre-defined time delay using an X-ray pulse.…”