[1] Univ St Andrews, Sch Chem, St Andrews KY16 9ST, Fife, Scotland
[2] Diamond Light Source, Didcot OX11 0DE, Oxon, England
[3] Univ Birmingham, Sch Chem Sci, Birmingham B15 2TT, W Midlands, England
[4] Univ Highlands and Islands, Free Radical Res Facil, Inverness IV2 3BL, Scotland
[5] Argonne Natl Lab, Adv Photon Source, Xray Sci Div, Argonne, IL 60439 USA
[6] Univ Mons, Lab Thermodynam, Fac Polytech, B-7000 Mons, Belgium