Question

$C{N}^{-}$ is a strong field ligand. This is due to the fact that

• A. it carries a negative charge
• B. it is a pseudo halide
• C. it can accept electrons from metal species
• D. it forms high spin complexes with metal Species

Answer 1

Answer: (A)

Cyanide ion is strong field ligand because of the presence of negative charge which makes it a stronger a donor than CO but it also weak the effectiveness of $C{N}^{-}$ as a $\pi$ acceptor. Thus, $C{N}^{-}$ have the ability to form $\sigma -$ bond and $\pi -$ bond.