Luminescent Coordination Polymers Built Upon Cu₄X₄ (X=Br,I) Clusters and Mono‐ and Dithioethers

Abstract

This paper focuses on the syntheses, structures, and luminescence properties of 1D, 2D, and 3D coordination polymers built upon the tetranuclear Cu(4) X(4) clusters and mono- and dithioether assembling ligands. A review of the relevant literature is presented along with our own results stressing on the salient features of the interactions between the CuI salt as the starting material and the thioethers. Among the features, the solvato- (lost or gain of a monothioether or solvent molecule) and luminescence thermochromism (temperature dependence of the emission) of the solids, and the enhanced versatility of the CuI salt to form clusters of different nuclearity (Cu(2) I(2) , Cu(4) I(4) , Cu(6) I(6) ) and structures (closed cubane, partially open "flower-basket-like" cubane, and open cubane) upon the reaction conditions and ligands, are described. The steady state and time-resolved solid-state emission and excitation spectra (at 298 and 77 K) as well as the emission lifetimes are examined. Simple and apparently "innocent" modification may have a drastic effect on the polymer network and cluster structures, but this paper finds no obvious trend for the moment except for the ligand rigidity. The rhombic Cu(2) I(2) and closed-cubane Cu(4) I(4) clusters are the most encountered motifs whereas the open-flower-basket Cu(4) I(4) cubane and the hexagonal Cu(6) I(6) clusters are scarce.

Luminescent Complexes Containing Halogeno-bridged Dicopper(I) Unit {Cu2(µ-X)2} (X = Cl, Br, and I)

“…3,30 The pyridine complex [Cu 4 I 4 (py) 4 ] shows dual emission ascribed to MLCT from the {Cu 4 I 4 } core to the ³* orbital of pyridine at higher energy (ca. 450 nm: blue) and intracluster transition at lower energy (ca.…”

“…27,28,33 For these thioether complexes, the emission resulting from the intracluster transition is observed in the range of 500600 nm without CT emission. 30 Because the bonding orbital composed of unoccupied Cu 4s and 4p orbitals in {Cu 4 I 4 } is stabilized by metalmetal interaction, lower energy emission is expected for complexes with shorter Cu£Cu distances. Actually, the shift of emission maximum from 538 nm at 298 K to 599 nm at 77 K is observed corresponding to the decrease of Cu£Cu distances by ca.…”

Designs of 3-Dimensional Networks and MOFs Using Mono- and Polymetallic Copper(I) Secondary Building Units and Mono- and Polythioethers: Materials Based on the Cu–S Coordination Bond

“…Concurrently, the M-SR linkages where RS -is a thiolate have been employed in a somewhat less extent, but can clearly lead to MOFs and 3D coordination polymers, including copper as the metal (about 25 structures) [14][15][16][17][18][19][20][21][22][23][24][25][26][27]. Conversely, the weaker dative Cu(I):SRR' bond, where RSR' is either a cyclic or acyclic mono-or di-or polythioether have attracted less attention [28][29][30][31]. Although the number of 1D and 2D coordination polymers issued from copper-thioether ligand interactions are numerous [28][29][30][31] the number of reported 3D polymers is more scarce (about 20 examples).…”

The polynuclear complex Cu4I4py4 loaded in mesoporous silica: photophysics, theoretical investigation, and highly sensitive oxygen sensing application

“…Generally, L may be a base with simple structure as pyridine (C5H5N) or a binder with a more complex structure such as that of the type 1,4-bis (cyclohexylthiomethyl) benzene. 8 Particularly, the luminescent Cu4I4py4 cluster complex has been extensively studied by Ford, 1,9,10 and other researchers. 8,11 In toluene solution, and at room temperature, it presents two characteristic emission bands around 480 nm (High energy, HE with τ = 0.45 µs at 298 K) and 690 nm (Low energy, LE with τ = 10.6 µs at 298 K).…”

“…8 Particularly, the luminescent Cu4I4py4 cluster complex has been extensively studied by Ford, 1,9,10 and other researchers. 8,11 In toluene solution, and at room temperature, it presents two characteristic emission bands around 480 nm (High energy, HE with τ = 0.45 µs at 298 K) and 690 nm (Low energy, LE with τ = 10.6 µs at 298 K). 1 The first is attributed to excited state halide to ligand charge transfer (XLCT), and the second to a cluster centered triplet transition ( 3 CC) that is weakly influenced by the ligand.…”