Proposed bonding sites of Ir(C2H4)2 complexes on MgO that give an Ir−O coordination number of 2 or 3 corresponding to the bipodal (I) and tripodal (II) species. The atoms are labeled as oxygen (red), magnesium (green), iridium (blue), carbon (gray), and hydrogen (white).

ACS Catal. 2018, 8, 3489−3498