Über Tetraalkylammonium-polyvanadate.

Abstract

In the reaction of V2O5 with aqueous or alcoholic solutions of tetraalkylammoniumhydroxide the orange decavanadates (NR4)3H3Vio028; (NR4)4H2VIO028> (NR4)5HVio028, (NR4)6VLO028 and colourless metavanadates can be obtained. The tetrabutylammoniumsalt [N(C4H9)4]3HV40i2 is the first known metavanadate with discrete polyanion. Its molecular weight was determined by vapor pressure osmometry in chloroform. The Raman spectrum is identical with the spectrum of a sodium metavanadate solution. The vibration spectra of the compounds are discussed and partial assignments were made.

A new antiferromagnetic Dy6 oxido-material as a multifunctional aqueous phase sensor for picric acid as well as Fe3+ ions

“…The observed interatomic distances in [Dy6(μ6-O)(μ3-OH)8(H2O)12(NO3)6] 2+ are in agreement with the contraction of ionic radii along the row of trivalent lanthanide cations [44]. Not only do the mean metal-metal distances decrease [d(Dy1-Dy2) 3.5114(7), d(Dy1-Dy3) 3.5258(7)pm], but the metal-oxygen distances do too[50,51]. Although such type of cluster unit has been reported previously for basic perchlorates and iodides as in […”

“…This gives some insight into the protonation sites of this bridging O atom. The protonation is much lower as indicated by the predominantly strong peak [47][48][49][50]. The hydrogen bonds to the terminal O atoms diminish the force constants of the Dy=O bonds and hence the intensity reduction occurs.…”

51V FT-nmr investigations of metavanadate ions in aqueous solutions

“…(c) Preparation of [N(C4H9)4]~,H,Vlo0,,: this compound was prepared as reported in the l~terature (25,26) by dissolving either I. l g of V,O, (J. T. Baker Chemical Co.) in 250 mL of 0.1 N [(CH3)4NOH.5H20] (Eastman Organic Chemicals) solution or by dissolving 1.20 g of NaVO, (Canadian Scientific Products Ltd.) in 150 mL of solution containing 6.14 g of tetra-n butyl ammonium chloride (Eastman Organic Chemicals) and 4.0g of NaOH (Fisher Scientific Co.). Any residue was filtered out.…”

“…The absence of the 582 ppm resonance suggests that TBA ions preferentially stabilize the V,Og3-and/or V4OIz4-species through ion pair formation. Fuchs et al (25,26) determined the structure of a crystalline salt prepared from similar solutions. They reported the structure to be cyclic, consisting of four VO, tetrahedra sharing two oxygen corners to form a puckered eight-membered ring.…”

Thermal reactivity of decavanadates

“…Decavanadates with organic cations are an exception [1,2]. Decavanadates with organic cations are an exception [1,2].…”