In which of the following pairs, both the species are not...

i. Hybridization of N{H}_{3}\left[σ = 3, lp = 1\right]

$s{p}^{3}$ geometry : Tetrahedral



ii. Structures of $Xe{F}_{4}$ is square planar.



Structure of $Xe{O}_{4}$ is tetrahedral



So $Xe{F}_{4}$ and $Xe{O}_{4}$ are not isostructural.

iii. Structure of $SiC{l}_{4}$ is tetrahedral.



Structure of ${PCl}_{4}^{+}$ is tetrahedral.



iv. Diamond and SiC both are isostructural because both have tetrahedral arrangement and central atom is $s{p}^{3}$ hybridized.