SCl4 is not isostructural with SiCl4 because it shows a square planar structure due to the repulsion between lone pair and bond pair of electrons. SO42−,PO43−,NH4+shows tetrahedral structure because of sp3 hybridisation. Related Theory Isostructural species are those which have the same shape and hybridization. Isoelectronic species have the same number of electrons which is the sum of electrons of all the atoms present in the ion.