Syntheses, structures and properties of two molybdenum phosphates [(H 20P 8Mo V12 CdO 62) (C 4H 14N 3) 2] · 2C 4H 13N 3 · 8H 2O and [(H 2P 2Mo VI5 O 23) (C 4H 14N 3) (C 4H 15N 3) (H 3O)] · 3H 2O

Abstract

Two new molybdenum phosphates [(H 20P 8Mo 12CdO 62) (C 4H 14N 3) 2] · 2C 4H 13N 3 · 8H 2O ( 1) and [(H 2P 2Mo 5O 23) (C 4H 14N 3) (C 4H 15N 3) (H 3O)] · 3H 2O ( 2) have been synthesized under the hydrothermal conditions and structurally characterized by single crystal X-ray diffractions. The compound 1 crystallizes in the monoclinic, space group P2(1)/ n, a = 13.2728(6) Å, b = 22.1483(9) Å, c = 13.6274(7) Å, β = 103.491(2)°, Z = 2. The crystal structure of 1 contains the isolated [H 20Mo 12P 8O 62] 2− units around which the protonated diethylenetriamine ions, the non-protonated diethylenetriamines and lattice water are positioned, While the compound 2 crystallizes in the triclinic, space group P-1, a = 10.3069(7) Å, b = 10.9483(8) Å, c = 15.6859(14) Å, α = 95.768(3)°, β = 95.678(4)°, γ = 111.391(3)°, Z = 2.The crystal structure of 2 also contains the isolated polyanion units [H 2P 2Mo 5O 23] 4− around the protonated diethylenetriamine ions, lattice water and the protonated water molecules. By hydrogen bond interactions their polyanions of the compounds 1 and 2 are both interconnected to form pseudo three-dimensional molybdophosphate. Other characterizations by elemental analyses, IR spectra and fluorescent spectra are also described. The electrochemical behaviors of 1 and 2 have also been studied in detail by cyclic voltammograms.