Available student project - The signature of large-amplitude vibrational motions encoded into small polyatomic molecular spectra

Research fields

  • Atomic and Molecular Physics
Photodetachment spectrometer

Project details

Isomerization reactions that involve migrating hydrogen atoms often play a critical role in more complex chemical reactions, including dehydration of alcohols, hydration of alkenes, and the gas-phase combustion of hydrocarbons. The ultrafast time scales, small barriers to rearrangement, breaking/forming of bonds, make these processes challenging to investigate.

The simplest example is vinylidene (:C=CH2) which is a transient, reaction intermediate. It is more commonly recognised by its stable isomer form, acetylene (H-C≡C-H). The transition from vinylidene to acetylene requires one H-atom to move to the other side of the molecule, yet it occurs on the order of a few pico-seconds. The physics picture is a bound system interacting with a system of much higher density of states, a situation that appears in many different fields of physics. However, it now seems likely that the vinylidene structure corresponds to 2 – 3 exact eigen-states, each is given by a coherent superposition of both vinylidene and acetylene amplitudes. This form may exist for several microseconds.

This project will use a state-of-the art electron imaging spectrometer, with world-leading energy resolution, to examine the vinylidene transition state, to provide a definitive identification of large amplitude signature states proximal to the isomerization barrier. These signatures will provide a rational basis for future control of unimolecular chemical reactions.

Required background

Recommended, not required, some basic quantum mechanics (e.g. PHYS2013), thermodynamics (PHYS2020), spectroscopy (PHY3031).

Project suitability

This research project can be tailored to suit students of the following type(s)
  • 3rd year special project
  • PhB (2nd or 3rd year)
  • Honours project
  • Phd or Masters

Contact supervisor

Gibson, Stephen profile
Senior Fellow

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