Identification of Ge≡O Triple Bond in Ge6O- Cluster: Anion Photoelectron Spectroscopy and Theoretical Calculations

Unlike C≡O, which is common in coordination chemistry and organometallic chemistry, little is known about Si≡O or Ge≡O compounds. Here we report a Ge₆O^- cluster featuring a Ge≡O triple bond. The structural and chemical bonding properties of Ge₆O^-/0 are investigated using anion photoelectron spectroscopy and theoretical calculations. Two nearly degenerate isomers have been found for Ge₆O^-. The lowest-energy structure (6A) can be viewed as an O atom bonding with a tetragonal bipyramidal Ge₆. The second one (6B) can be considered as an O atom interacting with a capped trigonal bipyramidal Ge₆. Chemical bonding analyses reveal that Ge₆O^- (6A) can be viewed as a Ge≡O unit interacting with a σ antiaromatic C_2v symmetric tetragonal pyramidal Ge₅^3- moiety. Comparisons of the chemical bonding in Ge₆O^- (6A) with that in Ge₅CO^- and Ge₅MnO^- indicate the similar behavior of Ge≡O to C≡O and Mn≡O in its bonding to the Ge₅^3- and Ge₅^4- moieties.

Biocompatibility of a nanocomposite based on Aerosil 380 and carboxylated fullerene C60[C(COOH)2]3

Silica is silicon dioxide, which, depending on the production method, can exist in various amorphous forms with varying specific surface area, particle size, pore volume and size, and, as a result, with different physicochemical and sorption characteristics. The presence of silanol groups on the surface of silicas provides the possibility of its further functionalisation. In addition, the developed specific surface of Aerosil allows to obtain composites with a high content of biologically active substances. In this work, we studied the biocompatibility of a composite based on Aerosil 380 and carboxylated fullerene C₆₀[C(COOH)₂]₃, namely: haemolysis (spontaneous and photoinduced), platelet aggregation, binding to HSA, cyto- and genotoxicity, antiradical activity. Interest in the creation of this nanomaterial is due to the fact that carboxylated fullerenes have potential applications in various fields of biomedicine, including the ability to bind reactive oxygen species, inhibition of tumour development, inactivation of viruses and bacteria. The obtained composite can be used for the immobilisation of various drugs and the further development of drugs for theranostics.