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David Reed coauthored research on iridium.^[ref]

Iridium is the chemical element with atomic number 77 and symbol $\mathrm{Ir}$. It is a transition metal. It is a dense platinum-group metal with strong corrosion resistance. Iridium-containing complexes and oxides can serve as catalysts, illustrating how oxidation state and coordination change the behavior of a chemically resistant bulk metal.

John David Kennedy coauthored research with Norman Greenwood and David Reed on reactions of the octahydrotriborate anion with transition-metal complexes. The work characterizes a borallyl iridium product, connecting boron-hydride cluster chemistry with metal coordination.

A cluster fragment can bind a metal through more than one atom. Establishing that connectivity requires evidence about the actual product, rather than assuming that every boron-hydride reagent retains its starting geometry.^[ref]

Norman Greenwood coauthored research on the reactions of boron-hydride clusters with cobalt, rhodium, and iridium complexes. A reported borallyl iridium product illustrates how a cluster can become a multidentate ligand.

The chemistry extends the usual picture of a ligand as a single atom donating one electron pair. Several atoms of a cluster fragment can participate in bonding, so cluster identity and coordination mode must both be specified.^[ref]

For a neutral borane ${\mathrm{B}}_{\mathrm{n}}{\mathrm{H}}_{\mathrm{m}}$ with one terminal B–H bond assigned to each vertex, the skeletal electron number is $3n+m-2n=n+m$; an overall charge $q-$ adds $q$ electrons. Suitable twelve-electron correspondences areFor C, four BH contributions plus four additional hydrogens give $8+4=12$ electrons. For D, three BH contributions plus five additional hydrogens and the negative charge give $6+5+1=12$. They map to the tetrahedral and triangular low-vertex skeletons respectively. The neutral formal alternative for D is ${\mathrm{B}}_3{\mathrm{H}}_9$, also with twelve skeletal electrons.

The electron counting correspondence alone must not be read as evidence that the neutral boranes are isolable stable bulk materials. Low-vertex hydrogen-rich boranes can be transient; the triangular octahydrotriborate anion is the established practical three-boron example, whereas neutral ${\mathrm{B}}_3{\mathrm{H}}_9$ is a formal analogy rather than an equally established preparative product. The requested skeletal correspondence should be distinguished from a claim about comparable stability or isolation conditions.^[ref]