skip to main content

Title: Communication: Oscillating charge migration between lone pairs persists without significant interaction with nuclear motion in the glycine and Gly-Gly-NH-CH{sub 3} radical cations

Coupled electron-nuclear dynamics has been studied, using the Ehrenfest method, for four conformations of the glycine molecule and a single conformation of Gly-Gly-NH-CH{sub 3}. The initial electronic wavepacket was a superposition of eigenstates corresponding to ionization from the σ lone pairs associated with the carbonyl oxygens and the amine nitrogen. For glycine, oscillating charge migration (when the nuclei were frozen) was observed for the 4 conformers studied with periods ranging from 2 to 5 fs, depending on the energy gap between the lone pair cationic states. When coupled nuclear motion was allowed (which was mainly NH{sub 2} partial inversion), the oscillations hardly changed. For Gly-Gly-NH-CH{sub 3}, charge migration between the carbonyl oxygens and the NH{sub 2} lone pair can be observed with a period similar to glycine itself, also without interaction with nuclear motion. These simulations suggest that charge migration between lone pairs can occur independently of the nuclear motion.
Authors:
; ;  [1]
  1. Department of Chemistry, Imperial College London, London SW7 2AZ (United Kingdom)
Publication Date:
OSTI Identifier:
22304360
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 140; Journal Issue: 20; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; AMINES; CARBONYLS; CATIONS; EIGENSTATES; ELECTRONS; ENERGY GAP; GLYCINE; INTERACTIONS; MOLECULES; NITROGEN; NUCLEI; OSCILLATIONS; OXYGEN; RADICALS; SIMULATION; WAVE PACKETS