My research focuses on using atomistic simulation to investigate defects and diffusion in materials. In particular I am using molecular dynamics employing empirical pair potentials to investigate the behaviour of dislocations in uranium dioxide and their interactions with fission products in the fuel matrix. In addition to my work on nuclear fuels I am also studying lithium ceramic materials that have been proposed for use in the breeder blanket region of a fusion reactor using density functional theory.

Prior to taking up a position as a Research Associate with the Atomistic Simulation Group I was employed as a researcher at the Commissariat a l’Energie Atomique Saclay just south of Paris. During my time in France I studied the nucleation of Xe containing nanoclusters into bubbles in nuclear fuels, again using molecular dynamics.

My first postdoctoral position saw me acting as a Research Assistant in the Materials Department at Imperial College where I was tasked with using DFT to examine defects in semiconductor materials such as InGaAs. These simulations involved the use of special quasirandom structures to mimic the behaviour of a random alloy.

It was also in the Materials Department that I undertook my PhD. During my PhD I used a combination of lattice statics and dynamics and in particular Temperature Accelerated Dynamics to examine the behaviour of defects in MgAl₂O₄ spinel.

##Publications

• S. T. Murphy and N. D. M. Hine, "Point defects and non-stoichiometry in Li₂TiO₃ ", Chemistry of Materials 26 1629 (2014). doi:10.1021/cm4038473
• S. T. Murphy, E. E. Jay and R. W. Grimes, “Pipe diffusion around dislocations in UO₂”, Journal of. Nuclear Materials 447 143 (2014). doi:10.1016/j.jnucmat.2013.12.029
• P. A. Burr, S. T. Murphy, S. Lumley, M. R. Wenman and Grimes, R. W., “Hydrogen solubility in zirconium intermetallic second phase particles”, Journal of. Nuclear Materials 443 502 (2013). doi:10.1016/j.jnucmat.2013.07.060
• H. A. Tahini, A. Chroneos, S. T. Murphy, U. Schwingenschlögl and R. W. Grimes, “Antisites and anisotropic diffusion in GaAs and GaSb” Applied Physics Letters 103 142107 (2013). doi:10.1063/1.4824126
• H. A. Tahini, A. Chroneos, S. T. Murphy, U. Schwingenschlögl and R. W. Grimes, “Vacancies and defect levels in III-V semiconductors” Journal of Applied Physics 114 063517 (2013). doi:10.1063/1.4818484
• W.E. Lee, M. Gilbert, S.T. Murphy and R.W. Grimes, “Opportunities for advanced ceramics and composites in the nuclear sector”, Journal of the American Ceramic Society 96, 2005–2030 (2013). 10.1111/jace.12406
• S.C. Lumley, S.T. Murphy, P.A. Burr, R.W. Grimes, P.R. Chard-Tuckey and M.R. Wenman, “The stability of alloying additions in Zirconium”, Journal of Nuclear Materials 437, 122–129 (2013). doi:10.1016/j.jnucmat.2013.01.335
• * P.A. Burr, S.T. Murphy, S.C. Lumley, M.R. Wenman, and R.W. Grimes, “Hydrogen accommodation in Zr second phase particles: Implications for H pick-up and hydriding of Zircaloy-2 and Zircaloy-4”, Corrosion Science 69 1–4. 10.1016/j.corsci.2012.11.036
• S.T. Murphy and N.D.M. Hine, “Anisotropic charge screening and supercell size convergence of defect formation energies”, Physical Review B 87 094111 (2013). doi:10.1103/PhysRevB.87.094111
• H. Lu, S.T. Murphy, M.J.D. Rushton, D.C. Parfitt, R.W. Grimes, “Thermal conductivity and the isotope effect in Li₂O”, Fusion Engineering and Design, 87, 1834 (2012). doi:10.1016/j.fusengdes.2012.08.008
• S.T. Murphy, A. Chartier, L. Van Brutzel and J.P. Crocombette, “Title: Free energy of Xe incorporation at point defects and in nanovoids and bubbles in UO₂” Physical Review B, 85, 144102 (2012). doi:14410210.1103/PhysRevB.85.144102
• C.L. Bishop, S.T. Murphy, M.J.D. Rushton and R.W. Grimes, “The influence of dipole polarisation on threshold displacement energies in UO₂” Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions With Materials and Atoms, 274, 195 (2012). doi:10.1016/j.nimb.2011.11.023
• S.T. Murphy, P. Zeller, A. Chartier, L. Van Brutzel, "Atomistic Simulation of the Structural, Thermodynamic, and Elastic Properties of Li₂TiO₃ " Journal of Physical Chemistry C, 115, 21874 (2011). doi:10.1021/jp204678c
• S.T. Murphy, A. Chroneos, R.W. Grimes, C. Jiang and U. Schwinschlögl, “Phase stability and the arsenic vacancy defect in In_xGa_(1-x)As” Physical Review B, 84, 184108 (2011). doi:10.1103/PhysRevB.84.184108