[English]

Computational Simulations of Organic Semiconductors

(supervisor: Chris Finlayson)

Nature of project: theory, software

Available to full-time physicists or joint students.

Project description and methodology

Semiconducting polymers represent a technologically important class of organic materials.[1] The electronic structure of pi-orbitals in such polymers enables them to absorb light and to generate free charge-carriers, as is seen to occur in solar cells and in natural processes such as photosynthesis. The use of organic semiconductors in electronics and in photovoltaic/solar cells, as a low-cost alternative to silicon based materials, is currently an area of intense scientific research and environmental interest.

This project will use computational studies (commercially available quantum chemistry software[3]) to model/visualize the geometries and bonding structures of these molecules, and their associated orbital energy levels. These factors have a direct impact on our understanding of the function and performance of optoelectronic devices.

A successful project will develop beyond the above in one/some of the following directions:
The project may have scope to examine some issues relevant to current research in the area of organic semiconductors, such as the influence of molecule stoichiometry and isometry[4] on the electronic energy levels.

When considering where to take your project, please bear in mind the time available. It is preferable to do fewer things well than to try many and not get conclusive results on any of them. However, sometimes it is useful to have a couple of strands of investigation in parallel to work on in case delays occur.

Additional scope or challenge if taken as a Year-4 project: As an extension, the project may have scope to examine some issues relevant to current research in the area of organic semiconductors, such as the influence of molecule stoichiometry and isometry[4] on the electronic energy levels. I believe that the project would be ideal for 4th year students.

Initial literature for students:

  1. A. Moliton et al., Polymer International, vol.53, p1397–1412 (2004)
  2. C.R. McNeill et al., Adv. Mater, vol.21, p3840–3850 (2009)
  3. http://gaussian.com/
  4. L-P. Lu et al., Macromol. Chem. Phys. vol.214, p967 (2013)

Novelty, degree of difficulty and amount of assistance required

The project is not likely to feature any experimental component, and is therefore suitable for students interested in theory and/or computation. A basic understanding of chemistry and bonding in molecules would be distinctly advantageous.

Project milestones and deliverables (including timescale)

milestoneto be completed by
Familiarisation with theory and softwareChristmas
Generation of target simulationsend of February
Simulation phasemid-March
Analysis/results phaseEaster