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Title: Simultaneous observation of nuclear and electronic dynamics by ultrafast electron diffraction

Journal Article · · Science
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3]; ORCiD logo [4];  [2]; ORCiD logo [1]; ORCiD logo [3];  [5];  [6]; ORCiD logo [7]; ORCiD logo [3]; ORCiD logo [5]; ORCiD logo [6]; ORCiD logo [6]; ORCiD logo [6];  [7]; ORCiD logo [2]; ORCiD logo [6]
  1. SLAC National Accelerator Laboratory, Menlo Park, CA, USA., Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
  2. SLAC National Accelerator Laboratory, Menlo Park, CA, USA., Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA., Department of Chemistry, Stanford University, Stanford, CA, USA.
  3. Department of Physics and Astronomy, University of Nebraska–Lincoln, Lincoln, NE, USA.
  4. Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA., Department of Chemistry, Stanford University, Stanford, CA, USA., Biophysics Program, Stanford University, Stanford, CA, USA.
  5. Institut für Physik und Astronomie, Universität Potsdam, Potsdam, Germany.
  6. SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
  7. Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY, USA.

Simultaneous observation of nuclear and electronic motion is crucial for a complete understanding of molecular dynamics in excited electronic states. It is challenging for a single experiment to independently follow both electronic and nuclear dynamics at the same time. In this paper we show that ultrafast electron diffraction can be used to simultaneously record both electronic and nuclear dynamics in isolated pyridine molecules, naturally disentangling the two components. Electronic state changes (S1→S0 internal conversion) were reflected by a strong transient signal in small-angle inelastic scattering, and nuclear structural changes (ring puckering) were monitored by large-angle elastic diffraction. Supported by ab initio nonadiabatic molecular dynamics and diffraction simulations, our experiment provides a clear view of the interplay between electronic and nuclear dynamics of the photoexcited pyridine molecule.

Research Organization:
SLAC National Accelerator Laboratory, Menlo Park, CA (United States). Linac Coherent Light Source (LCLS)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Chemical Sciences, Geosciences & Biosciences Division; USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Scientific User Facilities Division; Volkswagen Foundation
Grant/Contract Number:
AC02-05CH11231; AC02-76SF00515; FG02-08ER15984; SC0014170
OSTI ID:
1630393
Journal Information:
Science, Journal Name: Science Journal Issue: 6493 Vol. 368; ISSN 0036-8075
Publisher:
AAASCopyright Statement
Country of Publication:
United States
Language:
English

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