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Titolo:
SYNTHESIS AND CHARACTERIZATION OF WATER-SOLUBLE, ALL-INORGANIC COMPOSITION, DAWSON-TYPE TRISUBSTITUTED HETEROPOLYTUNGSTATES - EFFECT OF ALKALI-METAL COUNTERCATIONS (LI, NA, K, AND CS) ON THE P2W15NB3O629- POLYOXOANION
Autore:
NOMIYA K; NOZAKI C; MIYAZAWA K; SHIMIZU Y; TAKAYAMA T; NOMURA K;
Indirizzi:
KANAGAWA UNIV,FAC SCI,DEPT MAT SCI HIRATSUKA KANAGAWA 25912 JAPAN KANAGAWA UNIV,FAC ENGN,DEPT APPL CHEM YOKOHAMA KANAGAWA 221 JAPAN
Titolo Testata:
Bulletin of the Chemical Society of Japan
fascicolo: 6, volume: 70, anno: 1997,
pagine: 1369 - 1377
SICI:
0009-2673(1997)70:6<1369:SACOWA>2.0.ZU;2-6
Fonte:
ISI
Lingua:
ENG
Soggetto:
ATOMICALLY DISPERSED IRIDIUM(I); OXIDE ANALOGS; CATALYST PRECURSORS; NMR; HETEROPOLYANIONS; (1,5-COD)IR.P2W15NB3O62(8-);
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
24
Recensione:
Indirizzi per estratti:
Citazione:
K. Nomiya et al., "SYNTHESIS AND CHARACTERIZATION OF WATER-SOLUBLE, ALL-INORGANIC COMPOSITION, DAWSON-TYPE TRISUBSTITUTED HETEROPOLYTUNGSTATES - EFFECT OF ALKALI-METAL COUNTERCATIONS (LI, NA, K, AND CS) ON THE P2W15NB3O629- POLYOXOANION", Bulletin of the Chemical Society of Japan, 70(6), 1997, pp. 1369-1377

Abstract

The water-soluble form of the Dawson-type trisubstituted tungstoheteropolyanion, B-alpha-P2W15Nb3O629-, was synthesized as its nona alkali-metal salts of Li, K, and Cs. Analytically pure compounds, obtained ashomogeneous colorless solids, had nonahydrate for the nonalithium (Li-9) salt, tetrahydrate for the nonasodium (Na-9) salt, trihydrate for the nonapotassium (K-9) salt and trihydrate for the nonacaesium (Cs-9)salt, respectively, after each was dried overnight at room temperature under 10(-3)-10(-4) Torr. TG/DTA analyses show that they can be madewith 25 water for the Li-9 salt, 23 water for the Na-9 salt, 9 water for the K-9 salt, and 8 water for the Cs-9 salt under atmospheric conditions. A compositional characterization was accomplished by complete elemental analyses and TG/DTA, and structural characterization was achieved by a combination of FT-IR and variable-temperature solid-state P-31 NMR and by both P-31 and W-183 NMR measurements at room temperature in D2O and DMSO-d(6) solutions. The amount of hydrated waters, solubility in solvents and ease of crystallization were significantly influenced by the alkali-metal countercations. These cation-dependent properties are useful for selecting polyoxoanion precursor favorable to thecrystallization of P2W15Nb3O629- supported organometallic complexes. The effects of the cations (li, K, Na, and Cs) on the P2W15Nb3O629- were observed as different hydrated structures of the polyoxoanion and its cation-dependent thermal stability in the solid state by a combination of TG/DTA and FT-IR measurements, and also as a spectral change ofthe downfiled P-31 Signal due to interactions of the polyoxoanion with the countercations and/or with hydrated waters by variable temperature (VT) solid-state GHD/MAS (PNMR)-P-31 spectroscopy.

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Documento generato il 05/12/20 alle ore 09:48:54