In the given complexes, the heteroleptic complexes is/are:
A. \([Co(NH_3)_6]^{3+}\)
B. \([Cr(H_2O)_6]^{3+}\)
C. \([Ni(Cl_2)(PPh_3)_2]\)
D. \([Co(NH_3)_4Cl_2]^+\)
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is option 2. C and D only.
Heteroleptic complex: A coordination complex in which the central metal ion is bound to more than one type of ligand.
Analysis of options:
A. \([Co(NH_3)_6]^{3+}\): All six ligands are \(NH_3\), making it homoleptic, not heteroleptic.
B. \([Cr(H_2O)_6]^{3+}\): All six ligands are \(H_2O\), making it homoleptic, not heteroleptic.
C. \([Ni(Cl_2)(PPh_3)_2]\): This complex has two \(Cl\) ligands and two \(PPh_3\) ligands, satisfying the definition of heteroleptic.
D. \([Co(NH_3)_4Cl_2]^+\): This complex has four \(NH_3\) ligands and two \(Cl\) ligands, making it heteroleptic.
Therefore, the correct answer is 2. C and D only.
Key points to remember:
- Heteroleptic complexes offer greater diversity in properties due to the different electronic and steric effects of various ligands.
- They are often more common in biological systems, where metal ions need to interact with different molecules efficiently.