THE NEW PHASE BA0.167F0.083WO3- A PRODUCT OF THE THERMAL-DEGRADATION OF THE HETEROPOLY KEGGIN COMPOUND BA2H[ALPHA-FEO4W12O36]CENTER-DOT-26H2O(0.29 )

Authors
WEINER H LUNK HJ ZIEMER B KOHNKE K PIETZSCH C
Citation
H. Weiner et al., THE NEW PHASE BA0.167F0.083WO3- A PRODUCT OF THE THERMAL-DEGRADATION OF THE HETEROPOLY KEGGIN COMPOUND BA2H[ALPHA-FEO4W12O36]CENTER-DOT-26H2O(0.29 ), Thermochimica acta, 244, 1994, pp. 93-103
Citations number
20
Categorie Soggetti
Chemistry Analytical
Journal title
Thermochimica acta → ACNP
ISSN journal
00406031
Volume
244
Year of publication
1994
Pages
93 - 103
Database
ISI
SICI code
0040-6031(1994)244:<93:TNPBAP>2.0.ZU;2-5
Abstract
The thermal degradation of the polyoxometallate Ba2H[alpha-FeO4W12O36] . 26H(2)O was investigated by means of X-ray heating patterns, therma l analysis (TG, DTG, DTA, DSC) and spectroscopic methods (IR, ESR, Mos sbauer). The formation of the new hexagonal phase Ba0.167Fe0.083WO3+0. 29 (alpha = 7.320, c = 7.389 Angstrom A) can be observed. The phase is stable at room temperature. Its structure is related to hexagonal tun gsten bronzes but differs from them due to the presence of oxygen in a ddition to barium and iron along the hexagonal channels. The high posi tive charge of the cations leads to the maximum contraction of the cel l parameter c.