Explaining the nature of the E-O chemical bond (E = Si, Ge, Sn) has been a great challenge for theoretical chemists during the last decades. Among the large number of models used for this purpose, the one based on hyperconjugative interactions sheds more light on the nature of chemical bonding in siloxanes. Starting from this concept, this study aimed to evaluate the impact of siloxane type hyperconjugative effects on the structural features of germoxanic and stannoxanic species and in addition to assess if p-d-like back-bonding interactions can also play important roles in determining the particular structures of these heavier analogues of ethers. Natural bond orbital deletion (NBO DEL) optimizations, carried out at the DFT level of theory, revealed that hyperconjugative effects dictate to a large extent the structural behavior of these species. Furthermore, this study points out that p-d back-bonding interactions also influence the equilibrium geometry of these species, although acting as a secondary electronic effect within the E-O-E moieties (E = Si, Ge, Sn).

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The reactivity of a germylene and a stannylene containing an O,C,O‐coordinating pincer‐type ligand [2,6‐(RO2S)2‐4‐tBuC6H2]– (R = tolyl) was investigated towards ortho‐benzoquinone. The effect of the bis(sulfonyl) O2S‐C‐SO2 pincer‐type ligand and the benzoquinone group on the stability of the resulting cycloadducts was studied through experimental and computational techniques. The structures of the obtained products were determined in solution and in the solid state by multinuclear NMR and IR spectroscopy, mass spectrometry and single‐crystal X‐ray diffraction. DFT calculations, carried out at the B3LYP‐D3/Def2‐TZVP and M11‐L/Def2‐TZVP levels of theory, were performed in order to bring further clarification concerning the nature of the chemical bonding and the coordination geometry of these species. In addition, the stability of the metallylenes towards hydrolysis and dimerization was assessed.

New chiral heteroleptic germanium(ii) and tin(ii) metallylenes were obtained using 1-(para-tolylsulfinyl)-3-tosyl-5-tert-butyl-benzene as a non-symmetric O,C,O-chelating pincer ligand.

The contrasting geometrical features between organic and inorganic counterparts of amines and oxanes are explained in terms of an offset between attractive (donor–acceptor) and repulsive (donor–donor) interactions. Natural bond orbital (NBO) calculations carried out at the density functional theory level of theory reveal that hyperconjugative effects in the organic amines and ethers are overcome by repulsive interactions occurring between the lone pair on the nitrogen/oxygen atom and the adjacent σ­(C–R) bond orbitals. Although displaying lower energies than in the corresponding organic derivatives, the LP­(X) → σ*­(E–R) (X = N, O; E = Si, Ge, Sn) interactions in heavier counterparts overcome the LP­(X)···σ­(E–R) repulsions, impacting thus their structural behavior. In addition, NBO deletion optimizations emphasize that among hyperconjugations, back-bonding effects of the LP­(X) → d­(E) type dictate to a lesser extent the anomalous structures of the inorganic amines and oxanes.

Formation of stable carbides during CO bond dissociation on small ruthenium nanoparticles (RuNPs) is demonstrated, both by means of DFT calculations and by solid state 13C-NMR techniques. Theoretical calculations of...