CAS: 15321-51-4 EC No: 239-359-5 MDL No: MFCD00151465 UN No: UN3179; Haz Class: 4.1 (6.1); Packing Group: II Crystalline Linear Formula: Fe₂(CO)₉ MW: 363.79 Melting Point: 100° (decomposes) Density (g/mL): 2.85