Dr Dorothy Duffy

Biography

• Radiation damage in fusion reactor materials
• The effects of electronic excitations on radiation damage
• Modelling organic/inorganic interfaces
• Modelling crystal growth and inhibition

Research Interest
My research is concerned with modelling materials and material processes using simulation techniques such as Molecular Dynamics (MD). Currently my main focus is on modelling radiation damage in materials for fusion reactors. I am developing a method for including the effects of electronic excitations, which are thought to be important for high energy radiation particles, in radiation damage simulations.

I am also interested the effect of organic molecules on inorganic crystal growth. Living organisms have a remarkable ability to control the shape and orientation of crystals, resulting in exceptionally tough minerals, or shells with intricate shapes. Complex organic molecules are known to play an important role in this control, but the detailed mechanism is not well understood. I model interfaces between organic monolayers and calcite crystals in order to gain insight into the growth control mechanism.

Other activities

• Teach 3C46 Materials Science course
• CCP5 committee member
• Joint appointment with UKAEA Culham

Recent Publications

J.H. Harding and D.M.Duffy,  “The Challenge of Biominerals to Simulations”  J.Mat. Chem. 16, 1105, (2006)
This feature article reviews the experimental data on the properties and formation of biominerals and discusses the current attempts to simulate these materials at atomic and meso length scales.

D.M.Duffy and J.H.Harding, “The Crystallisation of calcite clusters on self-assembled monolayers” Surf. Sci. 595, 151 (2005)
This paper describes simulations of calcite cluster crystallization on self-assembled monolayers with two different chain lengths and demonstrates an odd-even effect.

D.M. Duffy, A.M. Travaille, H. van Kempen and J.H.Harding,
"Effect of bicarbonate ions on the crystallization of calcite on self-assembled monolayers “ Phys. Chem. B 109, 5713, (2005)
This paper demonstrates the role of bicarbonate ions in influencing the orientation of calcite crystal growth on self-assembled monolayers

Biography

• BSc Durham University
• PhD Imperial College
• Daphne Jackson Fellow (1996 – 1998) Reading University
• Lecturer In Physics (UCL) since 2005

Research

Crystal growth occurs via steps and kinks on surfaces, as ions from solution attach to a kink on a surface step.  The image shows the top layer of a calcite crystal which has a step and 2 kinks. In this case an oxalate ion has attached to the kink instead of a carbonate ion, which disrupts subsequent crystal growth. This is one possible mechanism whereby additives can slow, or inhibit, calcite crystal growth and prevent limescale deposition in water pipes.