Deep-blue luminescent [{Ir(C^N)2}3(L)2]3+ coordination cages with structurally integral pyridyl-azo-phenyl groups can be reversibly photo-isomerised with no compositional change.

The racemic ligands (±)‐tris(isonicotinoyl)‐cyclotriguaiacylene (L1), or (±)‐tris(4‐pyridyl‐methyl)‐cyclotriguaiacylene (L2) assemble with racemic (Λ,Δ)‐[Ir(ppy)2(MeCN)2]+, in which ppy=2‐phenylpyridinato, to form [{Ir(ppy)2}3(L)2]3+ metallo‐cryptophane cages. The crystal structure of [{Ir(ppy)2}3(L1)2]⋅3BF4 has MM‐ΛΛΛ and PP‐ΔΔΔ isomers, and homochiral self‐sorting occurs in solution, a process accelerated by a chiral guest. Self‐recognition between L1 and L2 within cages does not occur, and cages show very slow ligand exchange. Both cages are phosphorescent, with [{Ir(ppy)2}3(L2)2]3+ having enhanced and blue‐shifted emission when compared with [{Ir(ppy)2}3(L1)2]3+.

Zirconium and hafnium metallocene dihalides based on simple polyphenyl cyclopentadienes are stable room-temperature lumophores with large Stokes shifts, emitting from states with substantial LMCT character. Their synthesis is described, including by a rapid solvent-free approach compatible with the lifetime of PET-active isotopes (89Zr). Preliminary experiments indicate the viability of these species as lumophores for fluorescence cell-imaging microscopy.

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Mononuclear and trinuclear bis‐cyclometallated IrIII complexes of the host ligands tris(4‐[4′‐methyl‐2,2′‐bipyridyl]methyl)cyclotriguaiacylene (L1) and tris(4‐(4′‐methyl‐2,2′‐ bipyridyl)carboxy)cyclotriguaiacylene (L2) have been prepared. Complexes [{Ir(ppy)2}3(L1)](PF6)3 (1.1), [{Ir(ppy)2}(L1)](PF6)3 (1.2), [{Ir(ppy)2}3(L2)](PF6)3 (2.1) and [{Ir(ppy)2}(L2)](PF6)3 (2.2) (where ppy=phenylpyridinato) showed distinct photophysical properties depending on the L ligand. Complexes featuring the L1 ligand were comparatively blue‐shifted in solution, with longer lifetimes and higher quantum yields. The mixed bis‐cyclometallated IrIII complexes [{Ir(ppy)2}{Ir(dFppy)2}2(L1)](PF6)3 (1.3), [{Ir(ppy)2}{Ir(dFppy)2}2(L2)](PF6)3 (2.3), [{Ir(ppy)2}2{Ir(dFppy)2}(L1)](PF6)3 (1.4) and [{Ir(ppy)2}2{Ir(dFppy)2}(L2)](PF6)3 (2.4) (where dFppy=2,4‐difluorophenylpyrinato) were also synthesised. Steady‐state and time‐resolved spectroscopy, along with electrochemical investigations, show that the Ir(III) chromophores within these mixed Ir‐environment species behave as isolated centres, with no energy transfer or electronic communication between them.