Investigating the structure, bonding, and energy decomposition analysis of group 10 transition metal carbonyls with substituted terminal germanium chalcogenides [M(CO)₃GeX] (M = Ni, Pd, and Pt; X = O, S, Se, and Te) complexes: insight from first-principles calculations

Context: This research focused on the theoretical investigation of transition metal carbonyls [M(CO)₄] coordinated with terminal germanium chalcogenides complexes [M(CO)₃GeX], where M represents Ni, Pd, and Pt and X represents O, S, Se, and Te labeled 1-15. While the notable complexes M(CO)₄ (where M = Ni, Pd, Pt) numbered 1, 6, and 11 are of significance, substituting one of the CO ligands in 1, 6, and 11 with a GeX ligand (where X = O, S, Se, or Te) result in substituted complexes (2-5, 7-10, and 11-15). Substituting of the CO ligand slightly alters these bond angles. Specifically, the ∠CMC bond angles for [Ni] complexes range from 111.9° to 112.2°, for [Pd] complexes from 111.4° to 111.7°, and for [Pt] complexes from 112.4° to 112.8°. These findings indicate a minor deviation from the tetrahedral geometry due to the influence of the new GeX ligand. Similarly, there is a slight change in the geometry of the metal complexes, where the ∠GeMC angles for [Ni] complexes are between 106.7° and 106.9°, for [Pd] complexes between 107.2° and 107.5°, and for [Pt] complexes between 105.9° and 106.4°. Comparing among the substituted GeX complexes, those containing GeTe exhibit a higher natural bond orbital (NBO) contribution from the Ge atom compared to the M atom. Consequently, based on the above observations, it can be inferred that GeX acts as an effective sigma donor in contrast to carbonyl compounds. Results of energy decomposition analysis (EDA) for the M-CO bond in 1, 6, and 11 and for the M-GeX bond in the other [M(CO)₃(GeX)] complexes where M = Ni, Pd and Pt. The percentage contribution of ΔE_elstat and ΔE_orb shows a relatively identical behavior for all ligands in case of each metal complexes.

Methods: Density functional theory (DFT) calculations were conducted using the B3LYP/gen/6-31G*/LanL2DZ level of theory to examine transition metal carbonyls [M(CO)₄] coordinated with terminal germanium chalcogenides complexes [M(CO)₃GeX], where M represents Ni, Pd, and Pt, and X represents O, S, Se, and Te labeled 1-15 utilized through the use of Gaussian 09W and GaussView 6.0.16 software packages. Post-processing computational code such as multi-wave function was employed for results analysis and visualization.