why is [PtCl4]2- square planar & [NiCl4]2- tetrahedral ?
- ?Lv 51 decade agoFavorite Answer
(PtCL4)2- has square planar geometry because it has 4 bonds and 2 lone pairs of electrons. Pt is one of those strange elements like S and P that has 6 regions of high electron density. Look at it like this: Draw Pt in the center, and put 4 Cl around it. Now each Cl comes in with 7 electrons and Pt comes in with 6. Because there is a -2 charge you add two more electrons. So now you have each Cl bonded to Pt with a single bond which means 2 electrons. Now you have 4 extra electrons which means 2 lone pairs. hope that helps.
(NiCl4)2- is tetrahedral because it has 4 bonds and no lone pairs of electrons, which means it has 4 rergions of electron density.
- 5 years ago
It will be answered by CRYSTAL FIELD THEORY.