Scientific Reports 1, Article number: 59 (2011); Published: 10 August 2011; Updated: 17 December 2013

This Article contains an error in the Acknowledgements section:

“The operation of the microscope was supported by the Director, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, of the U.S. Department of Energy.” should read “The operation of the microscope was supported by the Director, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.”