Jones, Richard H. published the artcileColossal thermal expansion and negative thermal expansion in simple halogen bonded complexes, COA of Formula: C5H5ClIN, the publication is CrystEngComm (2014), 16(2), 237-243, database is CAplus.
The crystal structures of the simple monoclinic halogen-bonded complexes pyridine-ICl and pyridine-IBr have been redetermined using modern X-ray and neutron diffraction techniques. The representation quadric surfaces for the thermal expansion tensor have been found to consist of a hyperboloid of one sheet. Neg. thermal expansion occurs parallel to the crystallog. b axis, while there is colossal thermal expansion in a direction approx. parallel to the a* direction. These effects arise because of a decrease in the strength of an already weak C-H···X (X = Br, Cl) hydrogen bond with increasing temperature The decrease in strength of the hydrogen bonding originates because of the reduction in the strength of the halogen bond formed between the nitrogen atom and the IX moiety with increasing temperature Thus since at 298 K the I-X bonds are shorter than at 110 K, there will be a smaller partial neg. charge on the X halogen at 298 K, leading to a weaker C-H···X hydrogen bond.
CrystEngComm 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, COA of Formula: C5H5ClIN.
Referemce:
https://en.wikipedia.org/wiki/Iodide,
Iodide – an overview | ScienceDirect Topics – ScienceDirect.com