“…[1,2] Complexes of third row transition metal ions, such as Re I , Os II , Ir III and Pt II , are particularly appropriate for this purpose, because the high spin-orbit coupling constant associated with these metals efficiently promotes triplet radiative decay. [3][4][5] Although platinum porphyrins [1,[6][7][8] and a number of Pt II complexes based on bidentate coordinating aromatic ligands [9][10][11] have been reported in the literature as OLED emitters, there are relatively few examples of charge-neutral Pt II complexes with terdentate ligands that display efficient room-temperature luminescence in fluid solutions. [12][13][14][15][16][17][18][19] The most widely investigated class incorporate 6-phenyl-2,2′-bipyridine and derivatives that offer the metal an N ∧ N ∧ C coordination environment; [12][13][14][15][16]20] complexes of this type incorporating an acetylide ligand in the fourth coordination site have shown promise recently as phosphorescent OLED dopants.…”