Hassel, O. published the artcileStructure of the 1:1 compound pyridine-iodomonochloride, Formula: C5H5ClIN, the publication is Acta Chemica Scandinavica (1956), 696-8, database is CAplus.
cf. C.A. 48, 12115f; 50, 12592f. Pyridine-iodomonochloride, yellow monoclinic needles, m. 132°, space group P21/c, has parameters: a 4.25, b 12.29, c 14.07 A., β 94.4°, and bond distances I-Cl 2.51, N-Cl 2.26 A. Experiments show that the I, Cl, and N atoms are at least very nearly on a straight line, and suggest that the C atom opposite the N atom is also on this line, but do not appear to strengthen the suggestion that the “outer” halogen atom attains a strong neg. charge. Previous structure studies of ether-halogen addition compounds are compared with these on N compounds The strong interaction between the O or N atom and the nearest halogen atom is evident from the short separation between these atoms, this effect being greatest in the case of N. It is probable that electrons associated with the atoms forming the O-halogen or N-halogen bond are partially promoted to d orbitals.
Acta Chemica Scandinavica 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, Formula: C5H5ClIN.
Referemce:
https://en.wikipedia.org/wiki/Iodide,
Iodide – an overview | ScienceDirect Topics – ScienceDirect.com