Professor of Theoretical Organic Chemistry
1 South 0.19
Tel: +44 (0) 1225 386625
Prof Ian Williams
Physical and Theoretical Organic Chemistry
I teach physical organic chemistry to all years of the Chemistry programmes and run a computational chemistry lab course. My research is computational, and I head the Computational Chemistry section of the Department. I am a member of the IUPAC Subcommittee on Structural and Mechanistic Chemistry which has responsibility for the ICPOC international conferences on physical organic chemistry and am chairing the scientific committee for ICPOC21 to be held in Durham in 2012.
Modelling Chemical Reactivity
The tools of computational chemistry are applied to problems of chemical reactivity, with focus upon the transition state, which holds the key to understanding chemical reactivity and to interpreting experimental observations. Modern methods now allow realistic simulation of reactivity in large molecular systems, such as reactions in solution and in enzyme active sites.
- Transition states for reactions in solution
- Transition states for enzyme-catalysed processes
- Modelling to understand empirical probes of TS structure
- Modelling for catalyst design
Ruiz Pernía, J.J. and Williams, I. H., 2012. Ensemble-averaged QM/MM kinetic isotope effects for the SN2 reaction of cyanide anions with chloroethane in DMSO solution. Chemistry - A European Journal, 18 (30), pp. 9405-9414.
Williams, I. H., 2012. Kinetic isotope effects from QM/MM subset hessians: "Cut-off" analysis for SN2 methyl transfer in solution. Journal of Chemical Theory and Computation, 8 (2), pp. 542-553.
Williams, I. H., Pernia, J. J. R. and Tunon, I., 2011. Does glycosyl transfer involve an oxacarbenium intermediate? Computational simulation of the lifetime of the methoxymethyl cation in water. Pure and Applied Chemistry, 83 (8), pp. 1507-1514.
Williams, I. H., 2010. Catalysis: transition-state molecular recognition? Beilstein Journal of Organic Chemistry, 6, pp. 1026-1034.
Williams, I., 2010. Quantum catalysis? A comment on tunnelling contributions for catalysed and uncatalysed reactions. Journal of Physical Organic Chemistry, 23 (7), pp. 685-689.
Pernia, J. J. R., Tunon, I. and Williams, I., 2010. Computational simulation of the lifetime of the methoxymethyl cation in water. A simple model for a glycosyl cation: when is an intermediate an intermediate? Journal of Physical Chemistry B, 114 (17), pp. 5769-5774.
Greig, I. R., Macauley, M. S., Williams, I. H. and Vocadlo, D. J., 2009. Probing synergy between two catalytic strategies in the glycoside hydrolase O-GlcNAcase using multiple linear free energy relationships. Journal of the American Chemical Society, 131 (37), pp. 13415-13422.
Soliman, M. E. S., Ruggiero, G. D., Pernia, J. J. R., Greig, I. R. and Williams, I. H., 2009. Computational mutagenesis reveals the role of active-site tyrosine in stabilising a boat conformation for the substrate: QM/MM molecular dynamics studies of wild-type and mutant xylanases. Organic and Biomolecular Chemistry, 7 (3), pp. 460-468.
Soliman, M. E. S., Pernia, J. J. R., Greig, I. R. and Williams, I. H., 2009. Mechanism of glycoside hydrolysis: A comparative QM/MM molecular dynamics analysis for wild type and Y69F mutant retaining xylanases. Organic and Biomolecular Chemistry, 7 (24), pp. 5236-5244.
Kanaan, N., Ruiz Pernía, J. J. and Williams, I. H., 2008. QM/MM simulations for methyl transfer in solution and catalysed by COMT: ensemble-averaging of kinetic isotope effects. Chemical Communications
Buchanan, J. G., Ruggiero, G. D. and Williams, I. H., 2008. Dyotropic rearrangement of alpha-lactone to beta-lactone: a computational study of small-ring halolactonisation. Organic and Biomolecular Chemistry, 6 (1), pp. 66-72.