Topology of Other Functions

- In order to understand depleted homopolar bonds better Llusar et performed an ELF study of the N-N, 0-0 and F-F bonds. Deformation density maps are known to show a depletion of p between formally covalent bonds. However a topological analysis of the ELF function demonstrates that bond strength appears to be correlated with the disynaptic basin populations. From a qualitative point of view, the splitting of a disynaptic basin into two monosynaptic ones upon bond stretching is the signature of the covalent bond. 

Noury et alP reported on the details of the algorithms behind the generation of the 3D ELF grids, the assignment of ELF basins and integrations of properties over these basins. The issue of speed versus accuracy is discussed. 

Joubert et al used DFT to determine the structure and relative stability of Al-containing species involved in cryolitic melts. A concomitant topological analysis of ELF proved to be a powerful tool to obtain insight into the bonding properties. 

Fourre et al found that their ELF-based topological description of the chemical bond provides a deeper insight into the bonding evolution upon excitation, ionization, and electron attachment in carbonyl and imine compounds than the classical MO point of view. The changes occurring in the valence basin 

Fuentealba and Savin looked at the electronic structure of the ground state of monoxides MO and carbides MC2 with M an alkaline-earth metal atom. From their ELF study they learn that in the monoxides, and not in the carbides, a change in the type of bonding occurrs in going fi om Be to Ba. BeO is the only compound presenting some covalent bond character while the other oxides are clearly ionic. All carbides are ionic and bent. 

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