Single-Crystal to Single-Crystal Structural Transformation and Photomagnetic Properties of a Porous Iron(II) Spin-Crossover Framework
详细信息 查看全文
- 作者：Suzanne M. Neville ; Gregory J. Halder ; Karena W. Chapman ; Martin B. Duriska ; Peter D. Southon ; John D. Cashion ; Jean-Franç ; ois Lé ; tard ; Boujemaa Moubaraki ; Keith S. Murray ; Cameron J. Keper
- 刊名：Journal of the American Chemical Society
- 出版年：2008
- 出版时间：March 5, 2008
- 年：2008
- 卷：130
- 期：9
- 页码：2869 - 2876
- 全文大小：255K
- 年卷期：v.130,no.9(March 5, 2008)
- ISSN：1520-5126
文摘
The porous coordination framework material, Fe(NCS)2(bped)2·3EtOH, SCOF-3(Et) (where bpedis DL-1,2-bis(4'-pyridyl)-1,2-ethanediol), displays a spin-crossover (SCO) transition that has been stimulatedboth thermally and by light irradiation. The one-step thermal SCO (70-180 K) is sensitive to the presenceof molecular guests, with a more gradual transition (70-225 K) apparent following the desorption of ethanolmolecules that hydrogen bond to the spin centers. Additional intraframework hydrogen-bonding interactionsstabilize the vacant one-dimensional pore structure of the apohost, SCOF-3, despite a dramatic single-crystal to single-crystal (SC-SC) structural change upon removal of the guests. Comprehensive structuralanalyses throughout this transformation, from primitive orthorhombic (Pccn) to body-centered tetragonal(I4/mcm), reveal a flexing of the framework and a dilation of the channels, with an accompanying subtledistortion of the iron(II) coordination geometry. Photomagnetic measurements of the light-induced excitedspin state trapping (LIESST) effect have been used to assess the degree of cooperativity in this system.