Synthesis, crystal structure, thermal analysis, Hirshfeld surface analysis and density functional theory study of Ru3(CO)9(µ-Ph2AsCH2AsPh2)(AsPh3)

The reaction of Ru₃(CO)₁₀(µ-Ph₂AsCH₂AsPh₂) and arsine ligand (AsPh₃) afforded a new triruthenium cluster derivative, Ru₃(CO)₉(µ-Ph₂AsCH₂AsPh₂)(AsPh₃) (1). 1 was synthesised and characterised by elemental analysis, Fourier transform infrared, ¹H nuclear magnetic resonance (NMR) and ¹³C{¹H} NMR spectroscopy. The molecular structure of 1 was confirmed by single crystal X-ray diffraction (SXRD) analysis. The compound features a bidentate ligand of Ph₂AsCH₂AsPh₂ and a monodentate ligand of AsPh₃ that occupy the equatorial positions at Ru atoms. The thermal decomposition of 1 investigated by the thermogravimetric-differential thermogravimetric (TG-DTG) technique involves three stages, with the final product being Ru atoms with a residual rate of 18.60% (calcd: 18.41%). Density functional theory (DFT) calculations were performed using the B3LYP hybrid exchange–correlation functional method, and the LanL2DZ pseudopotential on Ru with 6-31G basis was set for all other atoms. Assessment of bond lengths and angles between SXRD and DFT data demonstrated consistent values within expected ranges. Frontier molecular orbitals analysis and molecular electrostatic potential were also illustrated. The 2D fingerprint plot of Hirshfeld surface analysis reveals that H···H contact dominates the population with 38%. The interplay of intermolecular C–H···O hydrogen bond and C–H···π interactions were found to be effective in stabilizing the molecular structure.