1.5 Ultraviolet scanning
As shown in experiments 18.104.22.168 & 22.214.171.124, it has been seen that NI3 will dissolve with organic solvents giving a single iodine peak at around 300nm (depending on the solvent the NI3 is dissolved in.)
An number of attempts were made to produce NI3 by the use of pyrrole and pyridine and the reaction of the lone pair of electrons on the N to react with the iodine in NI3.
No NI3 was produced. It can be seen from this that once the iodine has dissolved in the solvent, it will not form NI3. This may be due to the lone pair on the hetro nitrogen being used within molecule's p systems or (and more likely) the energy required to form the compound is too high.
Experiments at lower temperatures (down to 0 °C) did not show any signs of NI3 formation, neither did experiments at raised temperatures.