Having Marilyn Olmstead as my PhD supervisor meant that I was encouraged to examine complicated compounds with crystallography. She never dissuaded me from attempting data collections but she often emphasized that I should optimize whatever variables that I could control, e.g., crystal selection, exposure time, temperature, etc. Under her watchful eye, I learned a great deal and managed to collect data on a challenging endohedral fullerene, Tb3N@C84[i]. This structure brought me to my first summer conference season, where I learned about synchrotron radiation and chemical crystallography. Seeing the light, on that first trip to the beamline, was a transformative experience for me and my career. Despite the intervening 15 years, I can still feel the intoxicating mix of excitement and trepidation that washed over me when we arrived at Beamline 11.3.1 on the Advanced Light Source in Berkeley, CA. Samples too weak to tell us anything on the lab source shouted their secrets to the world in the face of the synchrotron X-rays. Data collections which would take days were done in 90 minutes. Marilyn had taught me to optimize my crystallographic excursions to the fullest, I could not refuse this huge increase in flux. Furthermore, I learned that a single structure didn’t have to be the end of a structural story; with such quick data collections, the beamline offered a new possibility of observing structural responses to stimuli. I was hooked. Chemical crystallography at synchrotrons continues to evolve, as do the chemical systems that come to the beamlines. Difficult structures are still elucidated, using the available X-ray photon flux that is multiple orders of magnitude over a lab source. Beamlines also offer users the ability to choose a wavelength that suits the compound, which enables absolute structure determination as well as resonant diffraction experiments. However, where the beamlines shine brightest is in in situ diffraction. The combination of high photon flux with high brightness gives experimenters access to observing their compounds of choice subjected to their stimuli of choice: pressure, light irradiation, variable temperature, gas environment, electric and magnetic fields. This presentation will give a whirlwind tour of the capabilities of the leading chemical crystallography beamlines coupled to relevant anecdotes.

Seeing the light: In situ chemical crystallography at synchrotron beamlines

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.