Platonic Gold NanocrystalsThis work was supported by the Camille and Henry Dreyfus Foundation, Beckman Foundation, the National Science Foundation (CAREER) and Department of Energy. P.Y. is an Alfred P. Sloan Research Fellow. Work at the Lawrence Berkeley National Laboratory was supported by the Office of Science, Basic Energy Sciences, Division of Materials Science of the U.S. Department of Energy. We thank the National Center for Electron Microscopy for the use of their facilities.