cuprous ion
; dimer
; gold
; monomer
; Article
; binding affinity
; controlled study
; covalent bond
; density functional theory
; molecular interaction
; phosphorescence
; priority journal
; quantum yield
; reduction (chemistry)
; sensitization
; solid state
英文摘要:
Outer-shell s0/p0 orbital mixing with d10 orbitals and symmetry reduction upon cupriphication of cyclic trinuclear trigonal-planar gold(I) complexes are found to sensitize ground-state Cu(I)-Au(I) covalent bonds and near-unity phosphorescence quantum yields. Heterobimetallic Au4Cu2 {[Au4(μ-C2,N3-EtIm)4Cu2(μ-3,5-(CF3)2Pz)2], (4a)}, Au2Cu {[Au2(μ-C2,N3-BzIm)2Cu(μ-3,5-(CF3)2Pz)], (1) and [Au2(μ-C2, N3-MeIm)2Cu(μ-3,5-(CF3)2Pz)], (3a)}, AuCu2 {[Au(μ-C2,N3-MeIm)Cu2(μ-3,5-(CF3)2Pz)2], (3b) and [Au(μ-C2,N3-EtIm)Cu2(μ-3,5-(CF3)2Pz)2], (4b)} and stacked Au3/Cu3 {[Au(μ-C2,N3-BzIm)]3[Cu(μ-3,5-(CF3)2Pz)]3, (2)} form upon reacting Au3 {[Au(μ-C2,N3-(N-R)Im)]3 ((N-R)Im = imidazolate; R = benzyl/methyl/ethyl = BzIm/MeIm/EtIm)} with Cu3 {[Cu(μ-3,5-(CF3)2Pz)]3 (3,5-(CF3)2Pz = 3,5-bis(trifluoromethyl)pyrazolate)}. The crystal structures of 1 and 3a reveal stair-step infinite chains whereby adjacent dimer-of-trimer units are noncovalently packed via two Au(I)-Cu(I)metallophilic interactions,whereas 4a exhibits a hexanuclear cluster structure wherein two monomer-of-trimer units are linked by a genuine d10-d10 polar-covalent bond with ligandunassisted Cu(I)-Au(I) distances of 2.8750(8) A each-the shortest such an intermolecular distance ever reported between any two d10 centers so as to deem it a "metal-metal bond" vis-à-vis "metallophilic interaction." Density-functional calculations estimate 35-43 kcal/mol binding energy, akin to typicalM-Msingle-bond energies. Congruently, FTIR spectra of 4a show multiple far-IR bands within 65-200 cm-1, assignable to vCu-Au as validated by both the Harvey-Gray method of crystallographic-distance-to-force-constant correlation and dispersive density functional theory computations. Notably, the heterobimetallic complexes herein exhibit photophysical properties that are favorable to those for their homometallic congeners, due to threefold-to-twofold symmetry reduction, resulting in cuprophilic sensitization in extinction coefficient and solid-state photoluminescence quantum yields approaching unity (PdblPL = 0.90-0.97 vs. 0-0.83 for Au3 and Cu3 precursors), which bodes well for potential future utilization in inorganic and/or organic LED applications.
Galassi, R., School of Science and Technology, Chemistry Division, University of Camerino, Camerino, I-62032, Italy; Ghimire, M.M., Department of Chemistry, University of North Texas, Denton, TX 76203, United States; Otten, B.M., Department of Chemistry, University of North Texas, Denton, TX 76203, United States; Ricci, S., School of Science and Technology, Chemistry Division, University of Camerino, Camerino, I-62032, Italy; McDougald, R.N., Jr., Department of Chemistry, University of North Texas, Denton, TX 76203, United States; Almotawa, R.M., Department of Chemistry, University of North Texas, Denton, TX 76203, United States; Alhmoud, D., Department of Chemistry, Yarmouk University, Irbid, 21163, Jordan; Ivy, J.F., Department of Chemistry, University of North Texas, Denton, TX 76203, United States; Rawashdeh, A.-M.M., Department of Chemistry, Yarmouk University, Irbid, 21163, Jordan; Nesterov, V.N., Department of Chemistry, University of North Texas, Denton, TX 76203, United States; Reinheimer, E.W., Rigaku Oxford Diffraction, The Woodlands, TX 77381, United States; Daniels, L.M., Rigaku Oxford Diffraction, The Woodlands, TX 77381, United States; Burini, A., School of Science and Technology, Chemistry Division, University of Camerino, Camerino, I-62032, Italy; Omary, M.A., Department of Chemistry, University of North Texas, Denton, TX 76203, United States, Department of Chemistry, Yarmouk University, Irbid, 21163, Jordan
Recommended Citation:
Galassi R.,Ghimire M.M.,Otten B.M.,et al. Cupriphication of gold to sensitize d10-d10 metal-metal bonds and near-unity phosphorescence quantum yields[J]. Proceedings of the National Academy of Sciences of the United States of America,2017-01-01,114(26)