Controlled Dimerization and Bonding Scheme of Icosahedral M@Au₁₂ (M=Pd, Pt) Superatoms

Targeted syntheses of MM′Au 36 (PET) 24 (M, M′=Pd, Pt; PET=SC 2 H 4 Ph) were achieved by hydride‐mediated fusion reactions between [MAu 8 (PPh 3 ) 8 ] 2+ and [M′Au 24 (PET) 18 ] − . Single‐crystal X‐ray diffraction analysis indicated that the products have bi‐icosahedral MM′Au 21 cores composed of M@Au 12 and M′@Au 12 superatoms. Although the MM′Au 21 superatomic molecules correspond to O 2 in terms of the number of valence electrons (12 e), the distances between the icosahedrons were larger than that in the bi‐icosahedral Au 23 core of Au 38 (PET) 24 corresponding to F 2 and the spin state was singlet. These counterintuitive results were explained by a “bent bonding model” based on tilted (non‐orthogonal) bonding interaction between the 1P superatomic orbitals of M@Au 12 and M′@Au 12 superatoms.