What would be the structure of #ICl_2^(-)# ion?

1 Answer
Dec 30, 2017

Is the ion not linear? Electronic geometry is trigonal bipyramidal.


There are #3xx7_"valence electrons"+1_"negative charge"=22*"electrons"# to arrange over three centres. And, typically, we put the LEAST electronegative atom centrally...

And so....#Cl-I-Cl#, from left to right, chlorine has 1 bonding pair and bears 3 lone pairs, iodine has 2 bonding pairs, and bears 3 lone pairs, and the terminal chlorine has bonding pair and bears 3 lone pairs, as before.


Because iodine is associated with EIGHT electrons, i.e. 3 lone pairs, and it is assigned 2 bonding electrons, it bears a FORMAL negative charge. The chlorine atoms are each associated with 7 electrons, and hence these centres are formally neutral.