Pd8 Nanocluster with Nonmetal‐to‐Metal‐ Ring Coordination and Promising Photothermal Conversion Efficiency.

Constructing ambient‐stable, single‐atom‐layered metal‐based materials with atomic precision and understanding their underlying stability mechanisms are challenging. Here, stable single‐atom‐layered nanoclusters of Pd were synthesized and precisely characterized through electrospray ionization mass spectrometry and single‐crystal X‐ray crystallography. A pseudo‐pentalene‐like Pd8 unit was found in the nanocluster, interacting with two syn PPh units through nonmetal‐to‐metal ‐ring coordination. The unexpected coordination, which is distinctly different from the typical organoring‐to‐metal coordination in half‐sandwich‐type organometallic compounds, contributes to the ambient stability of the as‐obtained single‐atom‐layered nanocluster as revealed through theoretical and experimental analyses. Furthermore, quantum chemical calculations revealed dominant electron transition along the horizontal x‐direction of the Pd8 plane, indicating high photothermal conversion efficiency (PCE) of the nanocluster, which was verified by the experimental PCE of 73.3 %. Therefore, this study unveils the birth of a novel type of compound and the finding of the unusual nonmetal‐to‐metal ‐ring coordination and has important implications for future syntheses, structures, properties, and structure–property correlations of single‐atom‐layered metal‐based materials. [ABSTRACT FROM AUTHOR]