theory calculations. They display bright-orange to red room-temperature luminescence in fluid dichloromethane solutions with microsecond to submicrosecond ranges of emissive lifetimes and 0.03−3.79% quantum yields, originating mainly from 3IL and 3MLCT excited states. Compared with the emissivestate in Pt(L)Cl complexes, substitution of the coordinated Cl with C≡CC6H4R-4 in Pt(L)(C≡CC6H4R-4) complexes induces