1. Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
2. Central Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory, Harwell Campus, Didcot, Oxfordshire, OX11 0QX, UK
3. Syngenta Crop Protection AG, Münchwilen, Breitenloh 5,4333, Switzerland