Theoretical investigations of the chemical bonding in MM'O clusters (M, M' = Be, Mg, Ca).

Motivated by the known stability of the somewhat unusual BeO rhombus, which features a short Be-Be distance but no direct metal-metal bonding, we investigate the nature of the bonding interactions in the analogous clusters MM'O (M, M' = Be, Mg, Ca). CCSD/cc-pVTZ and CCSD(T)/cc-pVQZ calculations, amongst others, are used to determine optimized geometries and the dissociation energies for splitting the MM'O clusters into metal oxide monomers. The primary tools used to investigate the chemical bonding are the analysis of domain-averaged Fermi holes, including the generation of localized natural orbitals, and the calculation of appropriate two- and three-center bond indices.

Electronic Structure and Bonding Situation in MO (M = Be, Mg, Ca) Rhombic Clusters.

Quantum chemical calculations using ab initio methods at the CCSD(T) level and density functional theory have been carried out for the title molecules. The electronic structures of the molecules were analyzed with a variety of charge and energy decomposition methods. The equilibrium geometries of the MO rhombic clusters exhibit very short distances between the transannular metal atoms M = Be, Mg, Ca.

Model for photodegradation of polybrominated diphenyl ethers.

Polybrominated diphenyl ethers (PBDE) were, and in some countries still are, used as flame retardants for plastic materials. When released from plastics, PDBE cause harm to the environment. This creates the incentive for further investigation of the PBDE degradation.

On the mechanism of dihydrogen activation by frustrated Lewis pairs. Insights from the analysis of domain averaged Fermi holes and generalized population analysis.

The electron reorganization responsible for the facilitation of heterolytic splitting of H-H bond by frustrated Lewis pair (FLP) catalysts has been studied using the analysis of domain averaged Fermi holes and generalized population analysis. The analysis of electron structures of the species along the reaction path has revealed that the anticipated synchronicity of previously considered electron shifts of electron pair of the σHH bond to a vacant orbital on B and from the lone pair on the basic N site to an antibonding σHH* orbital is associated with the build up of extensive delocalized bonding that can conveniently be characterized in terms of multicenter bond indices. In addition, the detailed scrutiny of the IRC-dependence of the 2-center bond indices of the disappearing H-H bond resulted in the proposal of a simple heuristic measure of the efficiency of the FLP catalysts.