Phase relations in the K{sub 2}W{sub 2}O{sub 7}-K{sub 2}WO{sub 4}-KPO{sub 3}-Bi{sub 2}O{sub 3} system and structure of K{sub 6.5}Bi{sub 2.5}W{sub 4}P{sub 6}O{sub 34}

Journal Article · Mon Sep 15 04:00:00 EDT 2008 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2008.05.035· OSTI ID:21128460

Terebilenko, K V ^[1]; Baumer, V N ^[2]; Ogorodnyk, I V; Slobodyanik, N S ^[1]; Shishkin, O V ^[2]

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1. Inorganic Chemistry Department, Kiev University, Volodimirska Street 64, Kiev 01033 (Ukraine)
2. STC 'Institute for Single Crystals' NAS of Ukraine, 60 Lenin ave., Kharkiv 61001 (Ukraine)

The phase relations in the cross-section of the K{sub 2}W{sub 2}O{sub 7}-K{sub 2}WO{sub 4}-KPO{sub 3} containing 15 mol% Bi{sub 2}O{sub 3} were undertaken using flux method. Crystallization fields of K{sub 6.5}Bi{sub 2.5}W{sub 4}P{sub 6}O{sub 34}, K{sub 2}Bi(PO{sub 4})(WO{sub 4}), Bi{sub 2}WO{sub 6}, KBi(WO{sub 4}){sub 2} and their cocrystallization areas were identified. Novel phase K{sub 6.5}Bi{sub 2.5}W{sub 4}P{sub 6}O{sub 34} was characterized by single-crystal X-ray diffraction: sp. gr. P-1, a=9.4170(5), b=9.7166(4), c=17.6050(7) A, {alpha}=90.052(5){sup o}, {beta}=103.880(5){sup o} and {gamma}=90.125(5){sup o}. It has a layered structure, which contains {l_brace}K{sub 7}Bi{sub 5}W{sub 8}P{sub 12}O{sub 68}{r_brace}{sub {infinity}} layers stacked parallel to ab plane and sheets composed by potassium atoms separating these layers. Sandwich-like {l_brace}K{sub 7}Bi{sub 5}W{sub 8}P{sub 12}O{sub 68}{r_brace}{sub {infinity}} layers are assembled from [W{sub 2}P{sub 2}O{sub 13}]{sub {infinity}} and [BiPO{sub 4}]{sub {infinity}} building units, and are penetrated by tunnels with K/Bi atoms inside. FTIR-spectra of K{sub 2}Bi(PO{sub 4})(WO{sub 4}) and K{sub 6.5}Bi{sub 2.5}W{sub 4}P{sub 6}O{sub 34} were discussed on the basis of factor group theory. - Graphical abstract: Sandwich-like architecture of K{sub 6.5}Bi{sub 2.5}W{sub 4}P{sub 6}O{sub 34} prepared during high-temperature investigation of K{sub 2}W{sub 2}O{sub 7}-K{sub 2}WO{sub 4}-KPO{sub 3} system. It is organized from {l_brace}K{sub 7}Bi{sub 5}W{sub 8}P{sub 12}O{sub 68}{r_brace}{sub {infinity}} layers and potassium atom sheets.

• OSTI ID: 21128460
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 9 Vol. 181; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
BISMUTH OXIDES
CROSS SECTIONS
CRYSTALLIZATION
GROUP THEORY
INFRARED SPECTRA
LAYERS
MONOCRYSTALS
PHOSPHATES
PHOSPHOROUS ACID
POTASSIUM COMPOUNDS
TUNGSTATES
X-RAY DIFFRACTION