The number of metal-metal bonds in [Co₂ Fe₂(CO)₁₁ (η⁴-PPh)₂] is · ABC26IN1436
Subject: Inorganic Chemistry · Chapter: Organometallic Compounds · Topic: Metal Carbonyls · Exam: CSIR NET DEC 2015 · Marks: 2 · Difficulty: Easy
The number of metal-metal bonds in $\left[\mathrm{Co}_{2} \mathrm{Fe}_{2}(\mathrm{CO})_{11}\left(\eta^{4}-\mathrm{PPh}\right)_{2}\right]$ is
(a)3
(b)4
(c)5
(d)6
Answer
Answer: B ✓ checked by 4AB · confidence high
Explanation
Electron count: 2 Co (18) + 2 Fe (16) + 11 CO (22) + 2 μ₄-PPh (8) = 64. Four 18-electron metals need 72; the deficit 8 is made up by (72 − 64)/2 = 4 metal–metal bonds.