A highly emissive inorganic hexamolybdenum cluster complex as a handy precursor for the preparation of new luminescent materials

Abstract

The synthesis and characterisation of a new, highly luminescent inorganic cluster complex, (Bu4N)2[Mo6I8(NO3)6], are described. The complex possesses labile nitrato ligands and is therefore a useful precursor for the design of new luminescent materials. To exemplify this, functionalised polystyrene beads have been utilised as "polymeric ligands" to immobilise the molybdenum cluster complex.

Cellular internalisation, bioimaging and dark and photodynamic cytotoxicity of silica nanoparticles doped by {Mo6I8}4+ metal clusters

“…Firstly, similarly to their structural analogues, hexarhenium clusters [{Re 6 Q 8 }L 6 ] m (Q = S or Se), these complexes demonstrate high chemical and photostability of the cluster cores {Mo 6 X 8 } 4+ that are primarily responsible for their triplet excited state photoluminescence (i.e. 4,5,11,15 Additionally, the metal cluster complexes can also act as powerful photosensitisers in the singlet oxygen ( 1 O 2 ) generation, [5][6][7][8][16][17][18] which makes them especially interesting for applications associated with the generation of singlet oxygen in vivo, such as, for example, photodynamic therapy (PDT). Secondly, their broad emission spectra extend in the red/near infra-red region (from ∼550 to more than 950 nm) 4-13 overlapping the so called "optical tissue window" (650 − 900 nm), where the boundaries of the region are defined by the minimal light absorption of hemoglobin (< 650 nm) and water (> 900 nm).…”

“…[24][25][26] All together these properties make hexamolybdenum cluster complexes very attractive for biomedical applications (e.g. To avoid the possible exchange of the ligands L by water molecules or OHions and simultaneously achieve a biocompatibility, the molybdenum metal cluster complex can be encapsulated within an inert biocompatible carrier matrix, such as polystyrene (PS) micro-beads 11,18,26 or SiO 2 . 27 Despite the mentioned potential for biomedical applications, the known hexamolybdenum cluster complexes themselves are not ideally suited for these purposes.…”

Complexes of {W6I8}4+ Clusters with Carboxylates: Preparation, Electrochemistry, and Luminescence

“…Octahedral halide cluster complexes of Mo II and W II , [{M 6 (µ 3 ‐X) 8 }L 6 ] (M = Mo or W; X = Cl, Br or I; L = neutral or anionic ligands), are chemically robust constructions with outstanding photophysical properties; therefore, they are potentially useful for various applications . The most studied are the derivatives of molybdenum chloride and bromide (M = Mo; X = Cl, Br).…”

Triblock copolymer-based luminescent organic–inorganic hybrids triggered by heating and fluoroquinolone antibiotics

“…The reason for choice of hexamolybdenum halide clusters with the {Mo 6 X 8 } 4+ core and six additional terminal ligands as the inorganic luminophor is based on its unique metal-centered luminescence [9][10][11][12][13][14][15][16][17][18][19][20][21].…”

“…Previously published papers [6,8] exemplify correlation of the temperature-induced phase transitions in liquid crystals and in aqueous solutions of triblock copolymers with lanthanide-centered luminescence. The development of water soluble supramolecular systems, where luminescence of inorganic luminophor correlates with thermally triggered aggregation of water soluble polymers is of particular importance, since it opens new routes to sense such phase transitions in aqueous solutions through a luminescent response.The reason for choice of hexamolybdenum halide clusters with the {Mo 6 X 8 } 4+ core and six additional terminal ligands as the inorganic luminophor is based on its unique metal-centered luminescence [9][10][11][12][13][14][15][16][17][18][19][20][21].The enhanced response of the clusters luminescence to dioxygen [17,18] makes them promising building blocks for fiber optic probes. It is worth noting that literature data highlight, first of all, the change of inner-and outer-sphere environment as a powerful tool to tune Mo-centered luminescence by an apical ligands substitution [14][15][16] and counter-ions exchange [19,21].…”