Question

Which one of the following high-spin complexes has the largest CFSE (Crystal field stabilization energy)?

• A. [Mn(H2O)6]2+
• B. [Cr(H2O6)]2+
• C. [Mn(H2O)6]3+
• D. [Cr(H2O)6]3+

Answer 1

Answer: (D)

$Cr(H2O)6$3+

Answer 2

[Mn(H2O)6]2+ = 3 × (–0.4) + 2 × (0.6) = 0

[Cr(H2O)6]2+ = 3 × (–0.4) + 1 × (0.6) = 0.6 D0

[Mn(H2O)6]3+ = 3 × (–0.4) + 1 × (0.6) = 0.6 D0

[Cr(H2O)6]3+ = 3 × (–0.4) + 0 × (0.6) = 1.2 D0