Structural Fragments Izopolivolframat–Anions and Gibbs Energy of Formation
Journal Title: Фізика і хімія твердого тіла - Year 2015, Vol 16, Issue 3
Abstract
The method of mathematical modeling (program CLINP 2.1, Newton's method) on the basis of the pH-potentiometric titration data allowed to calculate concentration constants of isopolytungstate anions (IPTA) formation at different ionic forces (I = 0,01 0,5 M). Thermodynamic constants of IPTA formation were obtained as a result of processing by Pitzer method using the concentration constans. The standard Gibbs energy of isopolytungstate anions formation were calculated. The last ones allowed to estimate the thermodynamic probability of the reactions, that can be used in the synthesis of salts containing these anions. The structure of known isopolytungstates can be built from the combination of such fragments: WO, W2O, W3O, W4O and W5O. The calculation of standard Gibbs energy of these fragments formation allowed to characterize the structure of hexatungstate-anion W6O20(OH)26-, which does not contain three terminal oxygen atoms. Such approach of using Gibbs energy of building blocks was recommended for prediction of equilibrium constants values in the mathematical modeling.
Authors and Affiliations
G. M. Rozantsev
Optical Absorption of Chalcogenide Glass Ga2S3-La2S3 Doped with Erbium
The glasses of the La2S3-Er2S3-Ga2S3 system were synthesized from the melted samples which where quenched in to the cold 25% solution of NaCl. Their optical absorption spectra were studied in the range of 1.2–2.9 eV at 8...
The Influence of the Synthesis Temperature on Phase Composition and Structure of Tenary Compounds Obtained from the Powder Mixture of the TiH2-Al-C System
This paper presents results of an investigation of the features of phase and structure formation of a ternary compound during thermal sintering use of compacted TiH2-Al-C powder blends. The thermal sintering was carried...
The Lithium Power Sources Based on Porous Carbon Material
The paper describes the use of porous carbon material (PCM), obtained from plant raw materials as anode of lithium power source (LPS). It is established that the electrochemical parameters of LPS at current density of C/...
Morphological and Structural Characteristics of the Iron Fluoride Preparated by Solvotermal Synthesis
In this communication we demonstrate the fast and facile preparation of nanoparticles hydrated and anhydrous iron trifluoride by solvotermal synthesis using the surface active substances. The iron fluoride/acytelen black...
Effect of Yttrium Oxide Impurities on the Structure and Properties of Metallic Hafnium
The influence of yttrium oxide impurity content of 0 to 0.4 wt.% on the structure and microhardness metal hafniuminvestigated. It is shown that grain size decreases and the Microhardness of hafnium increases monotonicall...