Question

Transition metals have the electronic configuration $(n-1)d^{1-10}n{s}^{1-2}$. The $d-$orbitals are degenerate. Colour of transition metal ions is due to absorption of some wavelength. This result in:

• A. $d-s$ transition
• B. $s-d$ transition
• C. $s-s$ transition
• D. $d-d$ transition

Answer 1

Answer: (D)

$d-d$ transition

When a transition metal compound is formed, the degeneracy of $d-$orbitals is resolved given two sets of orbitals slightly differing in energy. Absorption of light causes the promotion of electrons from lower energy set of orbitals to higher energy set within the same $d-$subshell. This is called $d-d$ transition.