Arene chromium tricarbonyl complex
= Arene chromium tricarbonyl complex
A neutral <piano-stool complex> $\mathrm{Cr}(\eta^6\!\text{-arene})(\mathrm{CO})_3$, conventionally <chromium>(0), with 18 valence <electrons>. <arene> substitution changes <electron> density and carbonyl stretching frequencies.