How does InChI represent organometallic compounds?
No widely accepted means of representing organometallic substances exists. Ferrocene, for instance, may be drawn with the central iron atom connected to each of the two rings, to each of the atoms in the rings, to each of the bonds in the rings or not connected at all. The default approach taken by InChI is to represent the structure as the individual, interconnected components along with the separated, unconnected metal atoms. For a large majority of organometallic compounds, this provides a unique InChI. If a bonded organometallic structure representation is desired, however, it may be specified by selecting “Include bonds to metal”, which adds an extra ‘Reconnected’ layer to the end of the current InChI. This layer, however, may depend on drawing conventions. Note that in the InChI for the default representation, the layers are sectioned by ; to separate the information for each of the components. To minimize the length of the InChI, as the two cyclopentadienyl rings are identical b
