A series of six novel cluster complexes [M₆I₈(SAr^f)₆]²⁻ (M=Mo or W; SAr^f=p‐SC₆F₄‐C₆F₅, p‐SC₆F₄Cl, or p‐SC₆F₄CF₃) was prepared by exchange reactions between [Mo₆I₁₄]²⁻ or [W₆I₁₄]²⁻ and silver salts of the corresponding thiols and characterized by X‐ray single‐crystal diffraction and elemental analysis, NMR, ESI‐MS, and CV techniques. In the crystal structures all the thiolate ligands adopt an idiosyncratic orientation along one of the idealized three‐fold axes passing through two opposite μ₃‐I ligands and the centers of two opposite faces of the M₆ octahedra. This leads to shortened intramolecular C⋅⋅⋅I distances inside the cluster below 3.5 Å. The clusters exhibit red photoluminescence with relatively high quantum yield, up to 0.42 in the case of (Bu₄N)₂[W₆I₈(SC₆F₄CF₃)₆]. Moreover, all the compounds exhibit X‐ray luminescence; the close values of the maxima in the photo‐ and X‐ray induced emission spectra indicate that the luminescence is cluster‐centered.

Thermal properties of decafluorodiphenyl disulfide in the pure state and in the presence of copper and iron metals have been studied. A procedure has been proposed for the synthesis of symmetrical poly­fluorinated diaryl sulfides from diaryl disulfides by heating with iron at high temperature. The developed procedure has been utilized to obtain 1,1′-sulfanediylbis(pentafluorobenzene), 1,1′-sulfanediylbis[3,5,6-tri­fluoro-2,4-bis(trifluoromethyl)benzene], and some other symmetrical polyfluorinated diphenyl sulfides containing a hydrogen or chlorine atom or trifluoromethyl group at the para positions of the benzene rings in up to 84% yield.

We demonstrate that a series of perfluorinated para-oligophenylenes C₆F₅-(C₆F₄)_n-C₆F₅ (n = 1–3) produce exciplexes with N,N-dimethylaniline (DMA) in degassed X-irradiated n-dodecane solutions. The optical characterization of the compounds shows that their short fluorescence lifetimes (ca. 1.2 ns) and UV-Vis absorption spectra, overlapping with the spectrum of DMA with molar absorption coefficients of 2.7–4.6 × 10⁴ M⁻¹cm⁻¹, preclude the standard photochemical exciplex formation pathway via selective optical generation of the local excited state of the donor and its bulk quenching by the acceptor. However, under X-rays, the efficient assembly of such exciplexes proceeds via the recombination of radical ion pairs, which delivers the two partners close to each other and ensures a sufficient energy deposition. The exciplex emission is completely quenched by the equilibration of the solution with air, providing a lower bound of exciplex emission lifetime of ca. 200 ns. The recombination nature of the exciplexes is confirmed by the magnetic field sensitivity of the exciplex emission band inherited from the magnetic field sensitivity from the recombination of spin-correlated radical ion pairs. Exciplex formation in such systems is further supported by DFT calculations. These first exciplexes from fully fluorinated compounds show the largest known red shift of the exciplex emission from the local emission band, suggesting the potential of perfluoro compounds for optimizing optical emitters.