Sandwich-Type Phosphotungstates: Structure, Electrochemistry, and Magnetism of the Trinickel-Substituted Polyoxoanion [Ni3Na(H2O)2(PW9O34)2<
详细信息 查看全文
- 作者：Ulrich Kortz ; Israel M. Mbomekalle ; Bineta Keita ; Louis Nadjo ; and Patrick Berthet
- 刊名：Inorganic Chemistry
- 出版年：2002
- 出版时间：December 2, 2002
- 年：2002
- 卷：41
- 期：24
- 页码：6412 - 6416
- 全文大小：139K
- 年卷期：v.41,no.24(December 2, 2002)
- ISSN：1520-510X
文摘
The novel nickel-substituted, dimeric phosphotungstate [Ni3Na(H2O)2(PW9O34)2]11- (1) has been synthesized andcharacterized by IR spectroscopy, elemental analysis, and electrochemistry. X-ray single-crystal analysis was carriedout on Na11[Ni3Na(H2O)2(PW9O34)2]·21.25H2O, which crystallizes in the triclinic system, space group P
cr.gif">, with a =12.2467(6) Å, b = 16.6031(7) Å, c = 22.4017(12) Å, 
chars/alpha.gif" BORDER=0> = 73.9870(10)
, chars/beta2.gif" BORDER=0 ALIGN="middle"> = 87.6060(10), chars/gamma.gif" BORDER=0 > = 79.344(2), andZ = 2. The polyanion consists of two lacunary B-chars/alpha.gif" BORDER=0>-[PW9O34]9- Keggin moieties linked via three nickel(II) centersand a sodium ion. The structure of 1 is composed of two fused Keggin fragments that represent different Baker-Figgis isomers (chars/alpha.gif" BORDER=0>- vs chars/beta2.gif" BORDER=0 ALIGN="middle">-type). Electrochemical studies show that 1 exhibits a stable and reproducible voltammetricpattern, with a first wave featuring a chemically reversible four-electron/four-proton process. An investigation of themagnetic properties indicates that the three nickel centers exhibit ferromagnetic exchange interaction.
cr.gif">, with a =12.2467(6) Å, b = 16.6031(7) Å, c = 22.4017(12) Å, chars/alpha.gif" BORDER=0> = 73.9870(10), chars/beta2.gif" BORDER=0 ALIGN="middle"> = 87.6060(10), chars/gamma.gif" BORDER=0 > = 79.344(2), andZ = 2. The polyanion consists of two lacunary B-chars/alpha.gif" BORDER=0>-[PW9O34]9- Keggin moieties linked via three nickel(II) centersand a sodium ion. The structure of 1 is composed of two fused Keggin fragments that represent different Baker-Figgis isomers (chars/alpha.gif" BORDER=0>- vs chars/beta2.gif" BORDER=0 ALIGN="middle">-type). Electrochemical studies show that 1 exhibits a stable and reproducible voltammetricpattern, with a first wave featuring a chemically reversible four-electron/four-proton process. An investigation of themagnetic properties indicates that the three nickel centers exhibit ferromagnetic exchange interaction.