Synthesis, spectral and structural characterization of organic ammonium paratungstates
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View Archive Info| Field | Value | |
| Title |
Synthesis, spectral and structural characterization of organic ammonium paratungstates
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| Creator |
Morajkar, Sudesh M
Srinivasan, Bikshandarkoil R |
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| Subject |
Tetraoxidotungstate
Organic amine Paratungstate Raman spectra Crystal structure |
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| Description |
185-195
Dissolution of tungsten(VI) oxide hydrate (WO<sub>3</sub>·H<sub>2</sub>O) in aqueous organic amine (RNH<sub>2</sub> where R = methyl or ethyl, or <em>n</em>-propyl or isopropyl or <em>n</em>-butyl or <em>t</em>-butyl etc.) results in the formation of the tetrahedral tetraoxidotungstate(VI) species in solution. Slow evaporation of the reaction mixture to isolate the tetraoxidotungstates charge balanced by organic ammonium cations afforded organic ammonium paratungstates having formula (RNH<sub>3</sub>)<sub>10</sub>[H<sub>2</sub>W<sub>12</sub>O<sub>42</sub>]·xH<sub>2</sub>O. The presence of (WO<sub>4</sub>)<sup>2-</sup> species in solution and the [H<sub>2</sub>W<sub>12</sub>O<sub>42</sub>]<sup>10</sup><sup>-</sup> unit in the solid product is confirmed by the characteristic Raman spectra. In this paper, we report on the synthesis, Raman spectra, crystal structures and properties of two organic ammonium paratungstates <em>viz</em>. (MeNH<sub>3</sub>)<sub>10</sub>[H<sub>2</sub>W<sub>12</sub>O<sub>42</sub>]·12H<sub>2</sub>O <strong>1</strong> (MeNH<sub>2</sub> = methylamine) and (EtNH<sub>3</sub>)<sub>10</sub>[H<sub>2</sub>W<sub>12</sub>O<sub>42</sub>]·4H<sub>2</sub>O <strong>2 (</strong>EtNH<sub>2</sub> = ethylamine). Thermal decomposition of <strong>1</strong> or <strong>2</strong> at 800 °C results in the formation of monoclinic form of tungsten trioxide WO<sub>3</sub>. A comparative study of several paratungstates is described. |
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| Date |
2021-02-11T07:01:46Z
2021-02-11T07:01:46Z 2021-02 |
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| Type |
Article
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| Identifier |
0975-0975(Online); 0376-4710(Print)
http://nopr.niscair.res.in/handle/123456789/56203 |
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| Language |
en_US
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| Rights |
<img src='http://nopr.niscair.res.in/image/cc-license-sml.png'> <a href='http://creativecommons.org/licenses/by-nc-nd/2.5/in' target='_blank'>CC Attribution-Noncommercial-No Derivative Works 2.5 India</a>
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| Publisher |
NISCAIR-CSIR, India
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| Source |
IJC-A Vol.60A(02) [February 2021]
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