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New nanocomposite materials with UV-NIR blocking properties and hues ranging from green to brown were prepared by integrating inorganic tantalum octahedral cluster building blocks prepared via solid-state chemistry in a PMMA matrix. After the synthesis by the solid-state chemical reaction of the K4[{Ta6Bri12}Bra6] ternary halide, built-up from [{Ta6Bri12}Bra6]4− anionic building blocks, and potassium cations, the potassium cations were replaced by functional organic cations (Kat+) bearing a methacrylate function. The resulting intermediate, (Kat)2[{Ta6Bri12}Bra6], was then incorporated homogeneously by copolymerization with MMA into transparent PMMA matrices to form a brown transparent hybrid composite Ta@PMMAbrown. The color of the composites was tuned by controlling the charge and consequently the oxidation state of the cluster building block. Ta@PMMAgreen was obtained through the two-electron reduction of the [{Ta6Bri12}Bra6]2− building blocks from Ta@PMMAbrown in solution. Indeed, the control of the oxidation state of the Ta6 cluster inorganic building blocks occurred inside the copolymer, which not only allowed the tuning of the optical properties of the composite in the visible region but also allowed the tuning of its UV and NIR blocking properties. [ABSTRACT FROM AUTHOR]

Naproxen (Nap), a non‐steroidal anti‐inflammatory drug, and 5‐fluorouracil (5FU), an anticancer drug, were easily incorporated into a polyurea xerogel. Polyureas (PUr) were synthesized by one pot reaction via sol–gel chemistry. Soft segments were based on polyetheramine‐PEO and hard segments were based on a hexamethylene diisocyanate trimer (HDI). The final materials were characterized by Fourier transform infrared (FTIR) spectroscopy, small‐angle X‐ray scattering (SAXS), and differential scanning calorimetry (DSC). Polyurea can assume many forms revealing its versatility in terms of produced shapes. In good agreement with FTIR, SAXS studies showed a microphase separated structure arising from inter‐hard‐domain spacings, which remains unchanged after incorporation of the drugs. DSC analysis demonstrated that the PEO chain mobility was poorly affected after the drugs incorporation due to the solvation of the drugs through the network. The water uptake and the amount of drug released agree well, playing an important role for controlled Nap and 5FU release. This work opens positive perspectives for ocular drug delivery and wound management, due to the easy processability of the xerogel, which has high feasibility to be moldable as pharmaceutical devices for contact lenses and transdermal patches purposes containing distinct therapeutic agents. [ABSTRACT FROM AUTHOR]

Hybrid materials that combine diureasil matrices and octahedral molybdenum clusters have been synthesized to design lead‐, cadmium‐ and rare‐earth‐free emitters for lighting or optoelectronic applications. This association leads to homogeneous and stable hybrids, for which the emission color can be tailored in the entire visible range, including white light; this is thanks to effective energy transfers from the host to the nanocluster. [ABSTRACT FROM AUTHOR]

Five new cluster compounds based on [Mo6Bri8(CN)a6]2− and [Mo6Bri6Qi2(CN)a6]n− (Q = S, Se, n = 3, 4) cluster units have been synthesized and characterized. Structures were determined by X-ray single crystal diffraction techniques and measurements of relevant magnetic susceptibility and optical properties were carried out. [trans-Mn(H2O)2][Mo6Br8(CN)6] (1) crystallizes in the orthorhombic system (Imma space group) and contains 2D square-net-layers built-up from [Mo6Bri8(CN)a6]2− and [trans-M(H2O)2]2+ moieties. Csx[trans-(MnIIxMnIII1−x)(H2O)2][Mo6Br6Q2(CN)6] (Q = S (2) and Se (3)) crystallize in the Imma space group as well; their structures are strongly related to that of 1 with a 2D square net of cluster units and transition metals. They are based on [Mo6Bri6Qi2(CN)a6]3− (Q = S, Se) cluster units whose charge is counter balanced by Cs+ as well as Mn2+ and Mn3+ in high spin states. It is evidenced that the x content of the Cs+ counter-cation is equal to that of Mn2+ in order to maintain – along with (1 −x) Mn3+– 23 valence electrons per cluster and a 3− charge for the cluster unit. The two oxidation states Mn2+ and Mn3+ were confirmed by electron energy loss spectroscopy (EELS) measurements. (H3O)H[cis-Cd(H2O)2][Mo6Br6Q2(CN)6]–H2O (Q = S (4) and Se (5)) crystallize in the trigonal system (P3121 space group) and are based on [Mo6Bri6Qi2(CN)a6]4− (Q = S, Se) cluster units. In contrast to compounds 1–3, owing to the cis-position of the two water molecules around the transition metal, 4 and 5 exhibit a close-packed 3D structure based on an interpenetrated framework of cluster-based chains. In particular, it contains infinite chains alternating [Mo6Bri6Qi2(CN)a6]4− and H+ protons as linkers. Magnetic and optical properties are also reported as well as theoretical calculations to support the structural analysis and physical properties. Structural analogies with [Re6Qi8(CN)a6]4− based compounds are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Hybrid nanomaterials made of inorganic nanocomponents dispersed in an organic host raise an increasing interest as low‐cost solution‐processable functional materials. However, preventing phase segregation while allowing a high inorganic doping content remains a major challenge, and usual methods require a functionalization step prior integration. Herein, we report a new approach to design such nanocomposite in which ceramic‐like metallic nanocluster compounds are embedded at 10 wt % in organic copolymers, without any functionalization. Dispersion homogeneity and stability are ensured by weak interactions occurring between the copolymer lateral chains and the nanocluster compound. Hybrids could be ink‐jet printed and casted on a blue LED. This proof‐of‐concept device emits in the red‐NIR area and generates singlet oxygen, O2 (1Δg), of particular interest for lights, display, sensors or photodynamic based therapy applications. [ABSTRACT FROM AUTHOR]

Self-organizing processes are elegant ways to generate and control the nanostructuration of hybrid materials. We describe in this work the synthesis, self-organizing abilities and photo-physical properties of (nBu4N)2[Mo6Bri8(L)a6] clustomesogens containing 18 cyanobiphenyl (CB) mesogenic moieties spread equally around the metallic scaffold via aliphatic spacers. By controlling the spacer length and thus the mesogenic density around the rigid inorganic bulky scaffold, we tailored the morphology of hybrid supermolecular building blocks from rod-like to disk-like which strongly influenced their self-organizing abilities. The photophysical properties of hybrids were investigated in their glassy state and in solution. Temperature studies reveal different behaviours depending on the hybrid nanostructuration. Despite their isotropic nature, octahedral clusters offer numerous possibilities in the design of self-assembled hybrid materials showing strong luminescence properties, which is of particular interest in the fields of optics or optoelectronics. [ABSTRACT FROM AUTHOR]

Herein, two new octahedral molybdenum cyanide cluster compounds, namely [{Ni(NH3)6}4{Ni2(NH3)8}1][Mo6Br6Q2(CN)6]3·12H2O, Q = S (1) and Se (2), have been synthesized as single crystals by slow diffusion of a solution of nickel chloride into aqueous ammonia solutions of a K2Cs2[Mo6Br6Q2(CN)6] molybdenum cyanide cluster-based compound. Both 1 and 2 were structurally characterized by single-crystal X-ray diffraction. They are isostructural and crystallize in the cubic system (Im3̅m (no. 229); Z = 2, a = 18.147(1) Å, and V = 5976(1) Å3 and a = 18.188(2) Å and V = 6016(2) Å3 for 1 and 2, respectively). 1 and 2 are based on the association of [Mo6Bri6Qi2(CN)a6]4− (Q = S, Se) cluster anions with Ni2+ dimer-based cubic [Ni2(NH3)8]4+ and octahedral [Ni(NH3)6]2+ cations. The structure is based on 2-fold interpenetrated [{Ni(NH3)6}4{Ni2(NH3)8}1][Mo6Br6Q2(CN)6]3 frameworks related to each other by [½, ½, ½] translation. The unit cell is based on a body-centered cubic framework of cubic [Ni2(NH3)8]4+. The [Mo6Bri6Qi2(CN)a6]4− (Q = S, Se) cluster units are located in the middle of the edges and at the center of the faces of the cell. The [{Ni(NH3)6}]2+ cations are located at the center of the cubes of the a/2 edge. The dimers [Ni2(NH3)8]4+ are stabilized by hydrogen bonds between the cyanide ligands of the cluster unit and the hydrogen atoms of the ammonia molecules. Both compounds exhibit a weak antiferromagnetic coupling within the [Ni2(NH3)8]4+ dimer entities at low temperatures together with a paramagnetic behavior originating from the cations of the octahedral [{Ni(NH3)6}]2+ complexes. [ABSTRACT FROM AUTHOR]

We report the photoluminescence (PL) and cathodoluminescence (CL) properties of face-capped [Mo6Xi8La6]2− (X = Cl, Br, I; L = organic or inorganic ligands) cluster units. We show that the emission of Mo6 metal atom clusters depends not only on the nature of X and L ligands bound to the cluster and counter-cations, but also on the excitation source. Seven members of the AxMo6Xi8La6 series (A = Cs+, (n-C4H9)4N+, NH4+) were selected to evaluate the influence of counter-cations and ligands on de-excitation mechanisms responsible for multicomponent emission of cluster units. This study evaluates the ageing of each member of the series, which is crucial for further energy conversion applications (photovoltaic, lighting, water splitting, etc.). [ABSTRACT FROM AUTHOR]