Crystal and molecular structure of complex compound (C5H5)2Re(H)CuRe(H)(C5H5)2: A first direct proof of the formation of the Cu(I)Cu(I) bond

Cu4I4 Clusters Supported by P∧N-type Ligands: New Structures with Tunable Emission Colors

“…The Cu1A–Cu2A distances vary from 2.525(2) to 2.630(1) Å and are comparable to the equivalent Cu–Cu distance (2.576 Å) found in Cu 4 I 4 (dcpm) 2 . These Cu–Cu lengths are much shorter than those found in Cu 2 I 2 clusters coordinated with monodentate N-heteroaromatic ligands (2.872–3.303 Å) or diphosphine ligands (2.898 Å), but are comparable with those in bimetallic complexes supported by 1,2,3-triazole (2.530 Å), benzimidazoles (2.546 Å), 2-benzoyl pyridines (2.587 Å), 1,8-naphthyridine (2.61–2.63 Å), and related nitrogen donor ligands. − The steric constraints imposed by the bridging P ∧ N-ligands also influence the separation between A and B fragments in the five Cu 4 I 4 cores. Compounds 3 and 4 have the shortest distance between Cu1A–Cu2B (2.839(3) and 2.880(1) Å, respectively), whereas the longest separation is found in 5 (3.035(2) Å).…”

Tetranuclear Copper(I) Iodide Complexes of Chelating Bis(1-benzyl-1H-1,2,3-triazole) Ligands: Structural Characterization and Solid State Photoluminescence

“…The dinuclear compound 4b contains the planar Cu 2 I 2 rhombic core that was originally expected and is very similar in geometry to the central Cu 2 I 2 portion of 1 , 3 , and 4a . The Cu···Cu distance of 2.5303(7) Å (compared to 2.6857(8) Å in 4a ) is among the shortest in planar dinuclear Cu 2 (μ 2 -I) compounds such as those supported by bulky pyridine ligands (2.557 Å), benzimidazoles (2.546 Å), 2-benzoyl pyridines (2.587 Å), imidazolyl pyridines (2.592 Å), phenanthroline (2.609 Å), and others. − Separations shorter than 2.530 Å in planar Cu 2 I 2 are observed only for dinuclear compounds with bridging ligands such as diphosphino carbenes (2.356 Å) …”

“…The Cu 3 3 3 Cu distance of 2.5303(7) A ˚(compared to 2.6857(8) A ˚in 4a) is among the shortest in planar dinuclear Cu 2 (μ 2 -I) compounds such as those supported by bulky pyridine ligands (2.557 A ˚), 74 benzimidazoles (2.546 A ˚), 75 2-benzoyl pyridines (2.587 A ˚), 70 imidazolyl pyridines (2.592 A ˚), 76 phenanthroline (2.609 A ˚), 71 and others. [77][78][79] Separations shorter than 2.530 A ˚in planar Cu 2 I 2 are observed only for dinuclear compounds with bridging ligands such as diphosphino carbenes (2.356 A ˚). 80 The step-type arrangement (Figure 3) in cuprous iodide cluster chemistry is often obtained in discrete complexes with monodentate, 81,82 bidentate, 83,84 or tridentate [85][86][87][88][89][90][91] ligands.…”

Reactivity of Divalent Germanium Alkoxide Complexes Is in Sharp Contrast to the Heavier Tin and Lead Analogues

“…21,25,26 Compound 7 is the second example in which a Cu 2 X 2 unit (X = Cl, Br, I) possesses three-coordinate copper centers bound to another metal. 27 The other known example is [Cp 2 ReHCuI] 2 ; 27 however, instead of the standard planar Cu 2 I 2 arrangement, the Cu 2 I 2 unit is folded, resulting in a short Cu•••Cu′ distance of 2.552(4) Å, indicative of a formal Cu−Cu bond. 21,25,26 Other examples the Cu 2 X 2 unit with a M−Cu bond, but a higher coordination number at copper, include Mo(W)−S clusters, 28 Mo−Sb clusters, 29 an Fe−(CO) cluster, 30 vinylideneand aminocarbyne-bridged heterobimetallic complexes, 31,32 a centrosymmetric [Cu 4 I 8 ] 4complex, 33 and a Cu 2 X 2 unit coordinated at each copper by two SbPh 3 ligands.…”