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Imaging an unsupported metal-metal bond in dirhenium molecules at the atomic scale.

ABSTRACT: Metallic bonds remain one of the most important and least understood of the chemical bonds. In this study, we generated Re2 molecules in which the Re-Re core is unsupported by ligands. Real-time imaging of the atomic-scale dynamics of Re2 adsorbed on a graphitic lattice allows direct measurement of Re-Re bond lengths for individual molecules that changes in discrete steps correlating with bond order from one to four. Direct imaging of the Re-Re bond breaking process reveals a new bonding state with the bond order less than one and a high-amplitude vibrational stretch, preceding the bond dissociation. The methodology, based on aberration-corrected transmission electron microscopy imaging, is shown to be a powerful analytical tool for the investigation of dynamics of metallic bonding at the atomic level.

SUBMITTER: Cao K

PROVIDER: S-EPMC6968940 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Imaging an unsupported metal-metal bond in dirhenium molecules at the atomic scale.

Cao Kecheng K Skowron Stephen T ST Biskupek Johannes J Stoppiello Craig T CT Leist Christopher C Besley Elena E Khlobystov Andrei N AN Kaiser Ute U

Science advances 20200117 3

Metallic bonds remain one of the most important and least understood of the chemical bonds. In this study, we generated Re<sub>2</sub> molecules in which the Re-Re core is unsupported by ligands. Real-time imaging of the atomic-scale dynamics of Re<sub>2</sub> adsorbed on a graphitic lattice allows direct measurement of Re-Re bond lengths for individual molecules that changes in discrete steps correlating with bond order from one to four. Direct imaging of the Re-Re bond breaking process reveals ...[more]

PMID: 32010771

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