Alkynyl bridged cyclometalated Ir2M2 clusters: impact of the heterometal in the photo- and electro-luminescence properties

We report two unprecedent alkynyl bridging cyclometalated clusters [Ir2M2(ppy)(4)(mu-C CC6H4-OMe3)(4)] where M is Ag (2) and Cu (3), which display distinctive luminescence properties. While 2 features a green phosphorescence/electroluminescence nature located at the ppy ligands ((LC)-L-3), 3 shows an orange emission confined to the metals and alkynyl groups having a mixed L-3'C/L-3' MCT/(MMCT)-M-3 (L' = alkynyl) nature.