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A new organic-inorganic hybrid transition metal phosphate, Cu 1.5 Li(C 2 H 10 N 2 )P 6 O 18 ·7H 2 O, has been prepared and characterized by X-ray diffraction, spectroscopy (infrared, Raman, diffuse reflectance and UV–Vis) and thermal analysis (TG). In addition, its electrochemical behaviors, as well as its antioxidant and antibacterial activities, have been investigated. Its structure is built up by the alternate linkages between copper and phosphate polyhedra, forming puckered layers with intersecting 12-membered rings, in which the ethylenediammonium cations reside. This compound is the first framework structure constructed from cyclohexaphosphates and three distinct copper cations. Cyclic voltammetry study in an acetonitrile solution reveals the facile anodic oxidation of its organic part on a platinum disk and a progressive growing of a thin film, though the repetitive cycling of potential. The title compound was tested for its in vitro antioxidant activities by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), Ferrous chelating ability (FIC) and Ferric Reducing Power (FRP) methods. The antioxidant activity of Cu 1.5 Li(C 2 H 10 N 2 )P 6 O 18 ·7H 2 O was analyzed simultaneously with its antibacterial capacity against Escherichia coli, Salmonella typhimurium, Staphylococus aureus, Enterococcus feacium, Streptococcus agalactiae and Candida albicans. The tested compound showed significant antioxidant activities with low antibacterial properties. [ABSTRACT FROM AUTHOR]

A new cyclohexaphosphate with the Li 2 Na 2 CoP 6 O 18 ·12H 2 O (LNCP) composition was prepared via a simple process at room temperature. This compound was characterized using X-ray diffraction (XRD), Infrared and UV–visible spectroscopy, Thermal analysis (TG), Cyclic voltammetry and Impedance spectroscopy. The results show that the LNCP was phased with a monoclinic structure and C 2/ c space group. The crystal structure was solved by using 3893 independent reflections with a final R value of 0.055. The P 6 O 18 ring is centrosymmetrical. Its main geometrical features are those commonly observed in the atomic arrangements of cyclohexaphosphate. The atomic arrangement of this compound can be described by an organization in a three-dimensional framework, formed by the anions (P 6 O 18 ) 6− and polyhedra of lithium and sodium. This structure has channels where octahedral cobalt is housed. By means of a cyclic voltammetry study, it is shown that this substrate undergoes a multistep anodic oxidation, leading to a thin and compact electroactive deposit. The electrical conductivity was studied using two-probe impedance spectroscopy and results showed that the conductivity of LNCP at 518 K was equal to 1.74 × 10 −4 Scm −1 . [ABSTRACT FROM AUTHOR]