JEE Main · 2026 · 02 Apr 2026 · Shift 2 · Chemical Bonding and Molecular Structure

$\mathrm{SF}{}_4$ has five electron pairs about sulfur, four bonding and one lone pair, giving a see-saw ($AX4E$) shape. $\mathrm{IF}{}_4{}^{+}$ likewise carries four bond pairs and one lone pair on iodine and is see-saw, while $\mathrm{XeO}{}_2\mathrm{F}{}_2$ has four $\sigma$ domains and one lone pair on xenon and is also see-saw, so both match. $\mathrm{BrF}{}_4{}^{-}$ and $\mathrm{XeF}{}_4$ are square planar ($AX4E2$) and $\mathrm{CH}{}_4$ is tetrahedral, so none of these is isostructural. The species isostructural with $\mathrm{SF}{}_4$ are $\mathrm{IF}{}_4{}^{+}$ and $\mathrm{XeO}{}_2\mathrm{F}{}_2$.