Abstract
Modern valence bond theory, in its spin-coupled form, is used to investigate the bonding in fluorocyclophosphazenes. We find that the spin-coupled orbitals for the 'out-of-plane' pi system split into two sets. One of these consists of slightly deformed pr functions that are fairly tightly localised on N atoms. The other set consists of functions that are also associated with individual N atoms but which also show significant delocalisation onto the neighbouring P atoms. The pairs associated with a given N atom are predominantly singlet coupled. It is found that the d basis functions used here for phosphorus play only a minor role, as polarisation functions. The same is true for the d functions on nitrogen. The spin-coupled description of the bonding, which is intermediate between the simplistic zwitterionic and covalent models, may be envisaged as a sequence of highly polarised Ndelta--Pdelta+ bonds.
| Original language | English |
|---|---|
| Pages (from-to) | 1541-1545 |
| Number of pages | 5 |
| Journal | JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS |
| Volume | 94 |
| Issue number | 11 |
| Publication status | Published - 7 Jun 1998 |
Keywords
- MAIN GROUP ELEMENTS
- D-ORBITAL PARTICIPATION
- ELECTRONIC-STRUCTURE
- VALENCE BONDS
- MOLECULES
- PHOSPHORUS
- PHOSPHAZENE
- CHEMISTRY
- STABILITY
- POLYMERS