C.A.M. acknowledges support from AFOSR Awards FA9550-11-1-0275 and FA9550-09-1-0294, AOARD Award FA2386-10-1-4065, Department of the Navy/ONR Award N00014-11-1-0729, DoD/NSSEFF/NPS Awards N00244-09-1-0012 and N00244-09-1-0071, and the Non-Equilibrium Energy Research Center (NERC), an Energy Frontier Research Center funded by DoE/Office of Science/Office of Basic Energy Sciences Award DE-SC0000989. D.J.E. and E.A. acknowledge support from the DoD, Air Force Office of Scientific Research, National Defense Science and Engineering Graduate (NDSEG) Fellowship, 32 CFR 168a. M.R.J. acknowledges a Graduate Research Fellowship from the NSF. Portions of this work were carried out at beamline 12-ID-B at the Advance Photon Source (APS). Use of the APS, an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science by Argonne National Laboratory, was supported by the U.S. DOE under contract no. DE-AC02-06CH11357. Electron microscopy was performed at the EPIC facility of the NUANCE Center at Northwestern University.