Question

Are all isostructural species also isoelectronic?

Answer 1

Compounds having the same structure are isostructural compounds. It is not compulsory for the two crystals to have the same cell dimensions and the same chemical composition. Isoelectronicity effect is seen when two or more molecules have the same structure as well as the same electron configurations but differ by certain location in the structure and what specific elements are at.

Complete answer:
Different species having the same number of electrons are isoelectronic species whereas species having the same geometry are isostructural species. The species can be an element or a compound.
Isoelectronic species and isostructural species are not related. Not all the isoelectronic species are isostructural but some of the isoelectronic species may be isostructural. Like for example $C{O_2}$ and ${N_2}O$ are isoelectronic and isostructural but $N{H_3}$ and ${H_2}O$ are isoelectronic but they are not isostructural. In carbon dioxide, the atomic number of carbon is 6, and 8 is the atomic number of oxygen. So it has a total of 22 electrons present and it has linear molecular geometry. Nitrous oxide has a total of 22 electrons and has a linear geometry.
But in ammonia, there are 10 electrons present and have a trigonal pyramidal shape. Similarly, water has 10 electrons and 10 protons in the molecule and has tetrahedral shape geometry and Bent shape.

Note:
Atomic number is equal to the number of protons present in an atom or to the total number of electrons. Species having the same atomic mass are isobars species having the same atomic number are isotopic species. Same physical and chemical properties are observed in isotopes but same physical properties, different chemical properties are in isobars.