Octahedral\nvs Tiara-like Pd<sub>6</sub>(SR)<sub>12</sub> Clusters

Atomically precise Pd-thiolate clusters are well-known\nfor their\nwell-defined structures and diverse applications involving catalysis,\nsensors, and biomedicine. While many of these clusters have been studied,\ntheir molecular structures typically feature a tiara-like arrangement.\nIn this study, we present the first example of a non-tiara-like Pd-thiolate\ncluster: the octahedral Pd<sub>6</sub>(SC<sub>6</sub>H<sub>11</sub>)<sub>12</sub> (denoted as Pd<sub>6</sub>-Oct). The composition and\ngeometric structure of the cluster were characterized using electrospray\nionization mass spectrometry (ESI-MS) together with single-crystal\nX-ray diffraction (SXRD). Despite having a similar chemical composition\nto tiara-like Pd<sub>6</sub>(SC<sub>2</sub>H<sub>4</sub>Ph)<sub>12</sub> (denoted as Pd<sub>6</sub>-Tia), Pd<sub>6</sub>-Oct exhibits a distinctly\ndifferent geometric structure. Additionally, UV–vis–NIR\nabsorption spectroscopy combined with quantum chemical calculations\nprovided valuable insights into the electronic structures of these\nclusters. The excited-state dynamics, host–guest chemistry,\nand the catalytic properties of Pd<sub>6</sub>-Oct and Pd<sub>6</sub>-Tia were examined to compare their structure–property relationships.\nThis research represents significant advances in the synthesis and\nunderstanding of structure–property correlations in Pd-thiolate\nclusters.