Superatom Paramagnetism in Au102(SR)441-/0/1+/2+ Oxidation States

Gold nanoclusters show distinctive magnetic properties and electronic structure. Nanoclusters of sufficiently small size restructure geometrically to stabilize electronically (e.g., a Jahn-Teller effect), whereas geometric distortion may not be possible in larger nanoclusters. In this work, the charge-state-dependent magnetism of the Au-102(SR)(44)(1-/0/1+/2+) nanocluster is investigated through Evans method NMR measurements. The 2+ charge state is shown as paramagnetic. This suggests that the nanocluster does not distort geometrically to pair electrons. Because the nanocluster lies within the transition range of molecule-like to bulk-like properties, this suggests that the geometric stabilization that becomes important in larger magic number clusters may be resistant to electronically driven distortions observed in smaller nanoclusters.