Ce/Au(CN) 2 – ‐Based Coordination Polymers Containing and Lacking Aurophilic Interactions

New members of the Ln[Au(CN) 2 ] 3 · 3H 2 O and [ n Bu 4 N] 2 [Ln(NO 3 ) 4 Au(CN) 2 ] series Ln = Ce (CeAu 3 and CeAu respectively) are reported herein where their synthesis, structure and photoluminescence properties are discussed. The first is a 3‐D coordination polymer with aurophilic interactions of 3.35 Å and the latter is a 1‐D coordination polymer that lacks them. At 293 K both CeAu 3 and CeAu display characteristic Ce III ‐based emission at λ max = 393 nm (5d→ 2 F J ), however in CeAu 3 Au I ‐based emission ( λ max = 410, 1 MLCT) dominates the spectrum. At 77 K however, the dominant emission is Au I ‐based with characteristic emissions of λ max = 430 nm ( 1 MLCT) and 490 nm ( 3 MLCT). The key difference in the luminescence of these two materials can be rationalized in terms of their respective structures, through either the aurophilic network and lack thereof and/or the rigidity offered in the 3‐D structure of CeAu 3 .