Cluster compounds cobalt-ruthenium carbonyl

Many metal clusters are air-stable compounds. However those of the first transition metal series are in general more sensitive to air. Thus, binary carbonyl of ruthenium, rhodium, and iridium are rather air-stable species while those of iron, Fe3(CO)i2, and cobalt, Co4(CO)i2, rapidly decompose apparently via formation of the carbonates. 

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