We explore the UV photofragmentation dynamics of acetaldehyde cation in our latest paper published in PCCP. Single-photon VUV ionization was used to prepare cold acetaldehyde cations that are subsequently excited (and fragmented) by UV radiation. The photochemistry is surprisingly rich; we use velocity-map ion imaging to characterize four different photofragmentation channels across a broad range of wavelengths. The experiments are supported by complementary ab initio calculations. The article will appear in a special themed issue of PCCP on Photodissociation and Reaction Dynamics that will be published to celebrate the 65th birthday of former University of Bristol colleague Prof. Mike Ashfold.
You can read the paper here: 10.1039/c8cp06640j
Two positions are available for high school teachers to participate in summer research in Dr. Craig Murray’s laboratory in the Department of Chemistry at the University of California, Irvine (UCI). The Murray Group uses a variety of laser-based spectroscopic techniques to study fundamental photochemistry and reaction kinetics and has a particular interest in processes relevant to atmospheric chemistry. The ‘Teacher-in-Residence’ program comprises two parts:
- Four-week summer research. Teachers will work directly with Dr. Murray and his research group in the laboratory and participate in other research-related activities to obtain direct experience of an academic research environment. The scheduling can be flexible to work around other commitments (e.g. weeks need not be consecutive), but the research program is full-time (>30 hours per week).
- Class visit. Teachers will bring their students (limited to 30 total visitors) to campus for a day. We will provide tours of various research laboratories and host a symposium to discuss research, educational opportunities at UCI, and current issues in environmental and atmospheric chemistry.
The ‘Teacher-in-Residence’ program is funded through an NSF award (CHE-1566064). Participating teachers will receive a modest stipend during the summer and costs associated with the class visit will be covered. If you are interested in participating and experiencing a real academic research environment, or have any questions about the program, please contact Craig Murray (firstname.lastname@example.org) directly. The deadline for applications is May 11, 2018.
Our latest photodissociation dynamics paper has been published in PCCP. The new paper describes ion imaging and photofragment excitation spectroscopy experiments exploring the photochemistry of acetone. We identify ketene as a new primary photoproduct following excitation to S1 and suggest that a roaming mechanism may be responsible. The radical channel forming methyl and acetyl is characterized over a broad range of wavelengths and is dominated by dissociation on the T1 surface following intersystem crossing. Time-resolved measurements using a ps laser system at 266 nm, find an intersystem crossing rate that is surprisingly around six times slower than in acetaldehyde.
You can read the paper here: 10.1039/c7cp07320h
Our new paper published in J. Phys. Chem. A. combines broadband transient absorption spectroscopy with complementary ab initio calculations to explore the kinetics of the reactions of the simplest Criegee intermediate with a series of alcohols. The results of this study provide new insights into trends in Criegee reactivity.
You can read the paper here: 10.1021/acs.jpca.7b09773
Our most recent paper published in Phys. Chem. Chem. Phys. explores the photochemistry of chlorodiiodomethane (CHI2Cl), a precursor of chlorinated Criegee intermediates. Velocity map ion imaging experiments and high-level ab initio calculations were employed to characterize the photodissociation dynamics of CHI2Cl over a range of wavelengths. We further used transient absorption spectroscopy to measure the UV absorption spectrum of a chlorinated Criegee intermediate, ClCHOO, produced from the reaction of CHICl with O2.
Check out our paper here: 10.1039/C7CP06532A
This article was selected as part of the 2017 PCCP HOT Articles themed collection.
Congratulations to Liz, who successfully defended her PhD dissertation last week despite the best efforts of an antique laptop to derail her talk. The defense was concluded with the conferral of her ceremonial tool belt. It was also great to see Ben again, who belatedly received his. We also said farewell to Liz this week. Liz moves to New England, where she will begin a post-doctoral position at MIT, working with Profs. Bob Field and Christopher Cummins. We wish her every success in her new job!
We are delighted to welcome high school teachers Larry Sepulveda (Rosemead High School) and Linda Kazibwe-James (Whittier Christian School) to the group. Larry and Linda are participating in our NSF-funded ‘Teacher in Residence’ outreach program this year, and will be working with us in the lab for the next month. The program aims to provide high school teachers with hands-on experience of life in a research laboratory.
Last Saturday, Liz was hooded by Craig as a (soon-to-be) Doctor of Philosophy! The ceremony was held at the Bren Events Center and honored the hard work and achievements of the class of 2017. Craig did a great job with the hooding (no hats were knocked off!) and everyone’s efforts were rewarded with a champagne reception following the event.
Craig, Liz, and Dean Janda
Unofficially an official PhD!
Liz gives the experience two thumbs up!
Last week Craig and Sara traveled to Chicago for the 10th International Conference on Chemical Kinetics hosted by the University of Illinois at Chicago. This 4-day conference featured talks from many different areas of research including pyrolysis, catalysis, and atmospheric chemistry.
Sara presented a poster on the reactions of the simplest Criegee intermediate with inorganic acids and alcohols:
They also had many opportunities to try the fantastic food Chicago has to offer, and highly recommend the cheeseburger with egg and bacon at Au Cheval.
They also visited The Bean!
Many congratulations to Liz, whose work has been recognized with the award of the E.K.C. Lee Fellowship. The Lee Fellowship is named after Prof. Ed Lee, one of the department’s founding faculty members and is awarded “to support outstanding students in chemistry.”