Copper® iodide clusters

A somewhat different situation is presented by the pressure effects seen in the emission spectra of the rhenium(I) complex ReBr(CO)3(phen) and the copper(I) cluster Cu4I4py4 (where py = pyridine) and related species. The former displays strong MLCT emission in ambient temperature fluid benzene [35] solutions while the latter displays a strong emission from an cluster centered (CC) excited state assigned as having mixed d-to-s metal-centered and iodide-to-copper charge-transfer character [36]. In each case, the emission is markedly dependent on the rigidity of the medium, and... 

In a series of papers, Ford and co-workers described the photophysical and photochemical properties of these luminescent clusters in detail [46-58]. In addition to complexes 4a and 4b, time-resolved emission spectra of the tetranu-clear copper(I) iodide clusters [Qi4l4(L)4] with a series of substituted pyridines [L = 4-tert-butylpyridine (4c), 4-benzylpyridine (4d), pyridine-dj (4e), 4-phe-nylpyridine (4f), 3-chloropyridine (4g), piperidine (4h), P"Bu3 (4i)] have also been studied [49]. The photophysical data are summarized in Table 1. In general, in toluene solution at 294 K, the complexes revealed a low-energy emission at 678-698 nm and a weaker, higher energy emission at 473-537 nm. The emission spectrum of 4a in toluene at 294 K is shown in Fig. 2... 

Ag3CuIg]4 clusters, in which copper(I) is three coordinated, whereas silver(I) is four coordinated or both three and four coordinated, respectively, from the metal iodides and tetraphenylphosphonium iodide in acetonitrile solution, may also be seen as lending support to the hypothesis that the primary process at the solution-crystal interface is cation-halide packing, the naked metal ion diffusing into the appropriate interstices. 

The emission spectrum of compound 8 exhibits in the solid state at room temperature an intense emission at 558 nm after excitation at 371 nm. According to the photoluminescent properties of Cu4I4 clusters, the emission band might be assigned to a combination of iodide-to-copper charge transfer (LMCT) and d-s transitions by Cu—Cu interaction within Cu3 clusters. 

The same group also explored the reactivity of the two asymmetric dithioether ligands with cyclohexyl (L45) and phenyl (L46) end groups toward Cul.164 Reaction of 2 (cyclohexylmethylthio)-l-thiomorpholinoethanone L45 with copper(I) iodide afforded a ID channel-type coordination polymer [Cu4I4(L45)2]n 45, interconnected by cubane-like tetranuclear Cu4I4 cluster units (Scheme 24). The mean Cu-Cu distance within the cluster cubes amounts to 2.749 A at 173 K. 

It has been known that the reaction of copper(I) iodide with Lewis bases, such as aniline derivatives, produced complexes with single cubane-like CU4I4 cluster, in which the aniline derivatives act as the terminal ligands coordinating to the copper(I) centers [7-10]. Thus, it is reasonable to expect macrocyclic or extended complexes constructed by CU4I4 cluster units through replacing aniline derivatives with ditopic... 

Deprotonation of the alkyne-bridged clusters [RuCo2(CO)9( U3-RC=CH)] (lOOa-d) with triethylamine and further reaction with the organometallic halides [Cp(CO)2FeCl] (101), [Cp(CO)2RuCl] (102), [Cp(PPh3)NiCl] (103) and [Cp(CO)3 MoCl] (104) in presence of catalytic amounts of copper(I) iodide results in... 

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