Poleshschuk, O. K. published the artcileAb initio study of the bonding and nuclear quadrupole coupling in the Py-ICl complex, Category: iodides-buliding-blocks, the publication is Journal of Molecular Structure (1999), 513(1-3), 29-34, database is CAplus.
As a result of the ICl complexation with Py, the 14N- and 35Cl-NQR frequencies are shifted towards lower values and 127I-NQR frequency towards higher values. In order to explain this phenomenon, ICl, Py and Py-ICl complex have been subjected to Gaussian-94 anal. on the 6-31G** level of the theory. The ab initio calculations indicate a good correlation between the calculated and the exptl. e2Qqzz as well as the values of the asymmetry parameter and their shifts upon complexation. As follows from the Townes-Dailey approximation, increasing ionicity of the I-Cl bond implies a decrease in 35Cl- and 14N-NQR frequencies and an increase in the 127I-NQR frequency, which has been confirmed by both exptl. and calculated results. The increase in the ionic character of the I-Cl bond can be observed as an increase in the neg. charge on the chlorine atom and a decrease in the pos. charge on the iodine atom. A decrease in the e2Qqzz 14N can be explained by an increase in the population of the π orbital while the population of the σ orbital remains unchanged. Stability of ICl complexes is determined by the contribution of the unpopulated orbital of the acceptor and coupling between the populated orbitals of the acceptor and the donor. The frequency shifts have been explained by the redistribution of electron d. taking place on complexation.
Journal of Molecular Structure published new progress about 6443-90-9. 6443-90-9 belongs to iodides-buliding-blocks, auxiliary class Pyridines, name is Pyridine Iodochloride complex, and the molecular formula is C5H5ClIN, Category: iodides-buliding-blocks.
Referemce:
https://en.wikipedia.org/wiki/Iodide,
Iodide – an overview | ScienceDirect Topics – ScienceDirect.com