Chapter 22, Problem 22.90QP

Interpretation Introduction

Interpretation:

Using crystal field theory, the crystal field energy diagram of low-spin complex ${\left[Ru{\left(N{H}_3\right)}_5{H}_{2}O\right]}^{2+}$ has to be drawn and the number of unpaired electrons in it has to be identified.

Concept Introduction:

There are five d-orbitals in a metal ion. They have similar energy levels that they are degenerated. Under the influence of ligands during complex formation, the degeneracy in d-orbitals is destroyed that they are split into two sets of orbitals - one set having lower energy and the another set is higher in energy.  Crystal field splitting refers to the difference in energy levels between these two sets of d-orbitals.

When ligands approach the metal ion the degeneracy in d-orbitals of the metal ion is destroyed and they split into two different energy levels. In case of octahedral complex, the $d_{x^2-y^2}and{d}_{z^2}$ orbitals occupy higher energy level and the $d_{xy},d_{xz},d_{yz}$ orbitals occupy lower energy level.  The energy gap between these two set of orbitals is termed as crystal field splitting energy.