Gold-Coated Transition-Metal Anion [Mn13@Au20]- with Ultrahigh Magnetic Moment

Structures and magnetic properties of gold-coated transition-metal clusters [Mn13@Au20]- and [Co13@Au20]- are studied within the framework of gradient-corrected density functional theory. The gold coating can result in either an enhanced or an attenuated effect on the magnetism of the core clusters. For [Mn13@Au20]-, the total magnetic moment is greatly enhanced to as high as 44 μB, more than 20-fold higher than that of the bare Mn13- cluster. For [Co13@Au20]-, however, the gold coating gives rise to an attenuation effect which leads to a reduction of the magnetic moment to 20μB from 30μB of the bare Co13- cluster.