Exploring the Activation of Atomically Precise [Pt₁₇ (CO)₁₂ (PPh₃ ₈]²⁺ Clusters: Mechanism and Energetics in Gas Phase and on an Inert Surface

Atomically precise clusters such as [Pt 17 (CO) 12 (PPh 3 ) 8 ] x+ (x = 1,2) (PPh 3 is triphenylphosphine) are known as precursors for making oxidation catalysts.However, the changes occurring to the cluster upon thermal activation during the formation of the active catalyst are poorly understood.We have used a combination of hybrid mass spectrometry and surface science to map the thermal decomposition of [Pt 17 (CO) 12 (PPh 3 ) 8 ] (NO 3 ) 2 .High-resolution mass and ion mobility spectrometry together with DFT-based modeling were used to probe the sequence of fragmentation reactions and fragment structures generated upon collisional excitation of [Pt 17 (CO) 12 (PPh 3 ) 8 ] 2+ .This was compared with thermal desorption spectroscopy of [Pt 17 (CO) 12 (PPh 3 ) 8 ] (NO 3 ) 2 dropcast onto an inert graphite surface.In both cases, a characteristic sequence of CO and benzene desorption steps is observed followed at higher excitation energy by H 2 loss.This behavior is indicative of Pt-catalyzed C-H activation of phenyl groups during partial stripping of the ligand shell while the Pt 17 P 8 cluster core is retained.