CHEM News & Highlights

10/04/2024: New instrument paper describing the standard configuration for liquid phase X-ray scattering and spectroscopy at LCLS

The paper describes in detail the liquid jet endstation (LJE) used at LCLS. The LJE has been designed to explore photochemistry and biochemistry in solution-phase through a combination of X-ray solution scattering (XSS), X-ray absorption spectroscopy (XAS), and X-ray emission spectroscopy (XES). In this setup, an optical laser excites the sample, which is then probed by a hard X-ray pulse to observe structural and electronic changes at femtosecond timescales. The LJE facilitates consistent sample delivery to the X-ray interaction point using various liquid jets, allowing for the rapid replacement of thin samples with millimolar concentrations and small volumes at the LCLS's 120 Hz repetition rate. This paper offers a comprehensive overview of the LJE's design and the techniques it supports, focusing on the diagnostics needed for real-time monitoring of the liquid jet and the methods used to optimize spatiotemporal overlap for signal enhancement. Additionally, it discusses several scientific applications, demonstrating the LJE's versatility. The paper can be found here.

10/23/2023: New study from our department on the structure of iron under extreme conditions published in Science Advances

Roberto led a study at the MEC endstation of LCLS which obtained the first direct evidence of iron rearrangement under high pressures into low spin, resulting in a denser state. The results could have significant impact on our understanding about how what influences the evolution of habitable conditions in planets. The study is published in Science Advances.

05/18/2023: New study from gas phase ultrafast electron diffraction published in Nature Communications

Yusong and the gas phase photochemistry group just published the most recent study from a series of investigations on electrocyclic photochemistry using the MeV-UED instrument. Their results reveal some of the mechanistic reasons for an important property of this class of reactions, their stereospecificity. The study was published in Nature Communications. The SLAC news article can be found here. The paper is also highlighted on the DOE Basic Energy Sciences website.

05/08/2023: New study co-lead by scientists from our department and SSRL just published in Nature Communications

Roberto Alonso-Mori, Tim van Driel, and Kristjan Kunnus have a new paper demonstrating how valence-to-core emission lines in X-ray emission spectroscopy can be utilitzed to elucidate the details of photochemical reactions in transition metal compounds. The study was published in Nature Communications. The SLAC news article can be found here.

12/01/2022: Liquid sheet jet publication highlighted in news article

DJ Hoffman published a study characterizing extremely thin (< 1 micrometer) liquid sheet "sandwiches" he creates in a jet. The study was published in Langmuir. The SLAC news article can be found here.

09/01/2022: New publication from our department

Tim van Driel published a combined experimental and simulation study on impulsive nuclear and Raman scattering in liquid chloroform in PRL.

03/23/2022: Rule-following molecules provide the first direct confirmation of a half-century-old theory
LCLS and PULSE researchers image a conformer-specific photochemical reaction in real space and time.

03/23/2022: Scientists capture the fleeting transition of water into a highly reactive state
Using SLAC's ultrafast electron camera, LCLS scientists image the hydroxyl-hydronium complex in liquid water.