1. School of Chemistry, University of St. Andrews, North Haugh, St Andrews KY16 9ST, United Kingdom
2. Department of Chemistry, Colorado State University, 1872 Campus Delivery, Fort Collins, Colorado 80523, United States
3. ZEISS Research Microscopy Solutions, Carl-Zeiss-Straße 22, Oberkochen 73447, Germany
4. Carl Zeiss Microscopy Ltd, Cambourne, Cambridge CB23 6DW, United Kingdom