Anisotropic Metal–Metal Pauli Repulsion in Polynuclear d10 Metal Clusters

Abstract

<p>Metallophilicity has been widely considered to be the driving force for self-assembly of closed-shell d¹⁰ metal complexes, but this view has been challenged by recent studies showing that metallophilicity in linear d¹⁰-d¹⁰ dimers is repulsive. This is due to strong metal-metal (M-M′) Pauli repulsion (Wan, Q., <cite><em>Proc. Natl. Acad. Sci. U. S. A.</em></cite> 2021, <em>118</em>, e2019265118). Here, we study M–M′ Pauli repulsion in d¹⁰ metal clusters. Our results show that M-M′ Pauli repulsion in d¹⁰ polynuclear clusters is 6-52% weaker than in similar linear d¹⁰ complexes due to the anisotropic shape of (<em>n</em>+1)s-<em>n</em>d hybridized orbitals. The overall M-M′ interactions in closed-shell d¹⁰ polynuclear metal clusters remain repulsive. The effects of coordination geometry, relativistic effects, and the ligand’s electronegativity on M-M′ Pauli repulsion in polynuclear d¹⁰ clusters have been explored. These findings provide valuable guidance for the design and development of ligands and coordination geometries that alleviate M-M′ Pauli repulsion in d¹⁰ metal cluster systems.<br></p>