Identify the thermodynamically stable structure of $[(\eta^{5}\text{-}\mathrm{C_5H_5})\mathrm{Fe}(\mu\text{-}\mathrm{CO})(\mathrm{NO})]_{2}$
(a)
(b)
(c)
(d)
Answer
Answer: B ✓ checked by 4AB · confidence low
Explanation
Count per Fe: Cp 5 + linear NO 3 + two μ-CO (1 each) = 18, so there is no Fe–Fe bond. The stable isomer is the trans, CO-bridged dimer with linear NO, as drawn in (b).