Though CFT is used for explaining transition metal complexes yet it can also be used for explaining the variation of lattice energies of transition metal compounds. For example halides of bivalent metal ions of 3d-series `(MX_(2)` . It is found that in the crystal of such metal halides each metal ion is octahedrally surrounded by halides ions and vice-versa, hence these compounds can be treated at par with octahedral complexes. In the following figure, variation of lattice energy of `MX_(2)` is given with atomic number of metal ions.

In which of the following complexes, the metal ion has lowest ionic radius?

Options

A. `[Ti(H_(2)O)_(6)]^(2+)`
B. `[V(H_(2)O)_(6)]^(2+)`
C. `[Cr(H_(2)O)_(6)]^(2+)`
D. `[Mn(H_(2)O)_(6)]^(2+)`

Answer

B

Explanation

(a)`t_(2g)^(1,1,0)eg^(0,0)`
(b) `t_(2g)^(1,1,1)eg^(0,0)`
(c ) `t_(2g)^(1,1,1)eg^(0,1)`
(d) `t_(2g)^(1,1,1)eg^(1,1)`
As `t_(2g).e^(-)uarr,"size"darr` because ligands approach closer to C.A. But, as`e_(g)e^(-)uarr,"repulsions"uarr,"size"uarr`.