American scientists have isolated and characterized a Mackay 55-metal-atom two-shell icosahedron 
15 February 2016

Scientists from the University of Wisconsin (Madison, Wisconsin) and Los Alamos National Laboratory (New Mexico) have reported the first successful isolation and crystallographic characterization of a Mackay 55-metal-atom two-shell icosahedron, Pd55L3-CO)20 (L = PPri3).