Excited state absorption spectra of the tetranuclear cuprous iodide cluster Cu4I4(py)4 and related species

Synthesis, Photophysics, and Transient Absorption Spectroscopic Studies of Luminescent Copper(I) Chalcogenide Complexes. Crystal Structure of [Cu4(μ-dtpm)4(μ4-S)](PF6)2{dtpm = Bis[bis(4-methylphenyl)phosphino]methane}

“…Similar to 1 and 2 , 9a,b and the isostructural [Ag 4 (μ-dppm) 4 (μ 4 -E)] 2+ series, 9c-e the phosphorescence of 3 is assigned to originate predominantly from a ligand-to-metal charge-transfer LMCT [(S 2- ) → Cu 4 ] excited state, mixed with a copper(I)-centered (ds/dp) state. Similar assignments have also been suggested in other luminescent polynuclear d 10 thiolato, 1a,d,2d,4a,d,5d,,8j halo, 1a-c,e and alkynyl 8c,d,f-i,l systems.…”

“…It has been well-known that polynuclear d 10 complexes such as those of copper(I), silver(I), and gold(I) possess remarkable photophysical and photochemical properties. − Recently, we have reported a novel class of luminescent tetranuclear d complexes containing an unsubstituted μ 4 -bridging chalcogenide ligand, [M 4 (μ-dppm) 4 (μ 4 -E)] 2+ (M = Cu, 9a,b Ag;9c E = S, Se, Te). These complexes have been found to exhibit long-lived phosphorescence; the excited states of which have been assigned as an admixture of ligand-to-metal charge-transfer LMCT [(E 2- ) → M 4 ] and metal-centered MC (d−s/d−p) Cu(I) or Ag(I) character, supported by spectroscopic studies, and Fenske−Hall 9d and ab initio 9e molecular orbital calculations.…”

Construction of 1D and 2D Copper(I) Coordination Polymers Assembled by PhS(CH2)nSPh (n = 1, 2) Dithioether Ligands: Surprising Effect of the Spacer Length on the Dimensionality, Cluster Nuclearity and the Fluorescence Properties of the Metal–Organic Framework

“…Upon excitation at 360 nm, a strong emission band was observed for the tetranuclear adduct, 1 , with a maximum at 532 nm. Emissions in a similar spectral range have been observed for nitrogen‐substituted Cu 4 I 4 L 4 clusters and were attributed to an emission from a triplet cluster centred excited state ( 3 CC) 3b,13. In fact, this broad CC excited state emission is mixed in character with equal contributions of iodine to copper charge transfer (XMCT) and copper orbital centred (d→s) transitions 3b.…”

Near-infrared phosphorescence: materials and applications

“…However, configuration mixing of the filled nd-orbitals with the empty orbitals derived from higher energy (n + 1)s and (n + 1)p orbitals has been proposed to establish some weak metal-metal interactions. 39 The clusters of Cu(I) complexes, especially cubane-like [Cu 4 (X) 4 (L) 4 ] clusters, 250 have attracted considerable interest because of their dual emission and long phosphorescent t. [251][252][253][254] There are several examples of NIR phosphorescent [Cu 4 (X) 4 (L) 4 ] clusters (Cu16-Cu22) 255,256 (Fig. 30 and Table 2) reported by Ford et al X-Ray crystallography shows that these complexes have a ''cubane'' Cu 4 I 4 core with a single pyridine (py) bound to each Cu and short Cu-Cu distances (ave. 2.69 Å) despite the absence of formal covalent bonding between these d 10 centers in the ground state.…”