|
|||||
|
|
Revealing Excited-State Trajectories on Potential Energy Surfaces with Atomic Resolution in Real Time |
|
| Authors: | Dr Denis Leshchev Dr Andrew J S Valentine Dr Pyosang Kim Dr Alexis W Mills Dr Subhangi Roy Dr Arnab Chakraborty Dr Elisa Biasin Prof Kristoffer Haldrup Dr Darren J Hsu Dr Matthew S Kirschner Dr Dolev Rimmerman Dr Matthieu Chollet Dr J Michael Glownia Dr Tim B van Driel Prof Felix N Castellano Prof Xiaosong Li Prof Lin X Chen |
| Institution: | 1. Department of Chemistry, Northwestern University, IL 60208 Evanston, USA;2. Department of Chemistry, University of Washington, WA 98195 Seattle, USA;3. Department of Chemistry, Northwestern University, IL 60208 Evanston, USA
Chemical Science and Engineering Division, Argonne National Laboratory, IL 60439 Lemont, USA;4. Department of Chemistry, North Carolina State University, NC 27695-8204 Raleigh, USA;5. Physical Sciences Division, Pacific Northwest National Laboratory, WA 99352 Richland, USA;6. Physics Department, Technical University of Denmark, 2800 Kongens Lyngby, Denmark;7. SLAC National Accelerator Laboratory, Stanford University, CA 94025 Menlo Park, USA |
| Abstract: | Photoexcited molecular trajectories on potential energy surfaces (PESs) prior to thermalization are intimately connected to the photochemical reaction outcome. The excited-state trajectories of a diplatinum complex featuring photo-activated metal–metal σ-bond formation and associated Pt?Pt stretching motions were detected in real time using femtosecond wide-angle X-ray solution scattering. The observed motions correspond well with coherent vibrational wavepacket motions detected by femtosecond optical transient absorption. Two key coordinates for intersystem crossing have been identified, the Pt?Pt bond length and the orientation of the ligands coordinated with the platinum centers, along which the excited-state trajectories can be projected onto the calculated PESs of the excited states. This investigation has gleaned novel insight into electronic transitions occurring on the time scales of vibrational motions measured in real time, revealing ultrafast nonadiabatic or non-equilibrium processes along excited-state trajectories involving multiple excited-state PESs. |
| Keywords: | Excited States Intersystem Crossing Platinum Transition-Metal Complexes Ultrafast Spectroscopy |