Q68 · CSIR NET Chemistry, December 2013
Paper: CSIR NET December 2013 · Subject: Inorganic Chemistry · Chapter: Organometallic Compounds · Topic: Metal Carbonyls · Marks: 2 · Difficulty: Hard
The bond order of the metal-metal bond in the dimeric complex $\left[\mathrm{Re}_{2} \mathrm{Cl}_{4}\left(\mathrm{PMe}_{2} \mathrm{Ph}\right)_{4}\right]$ is
(a)4.0
(b)3.5
(c)3.0
(d)2.5
Answer
Answer: C ✓ checked by 4AB · confidence high
The source book printed B; on checking, C is correct — see the explanation.
Printed B; 3.5 belongs to the one-electron oxidised cation.
Explanation
[Re₂Cl₄(PMe₂Ph)₄] is Re(II)–Re(II), d⁵d⁵: σ²π⁴δ²δ*² gives bond order (8 − 2)/2 = 3.0.
Study loop for Organometallic Compounds