Syntheses and X-ray Powder Structures of Two Zinc Propylenebis(phosphonates)
详细信息 查看全文
- 作者：Damodara M. Poojary ; Baolong Zhang ; and Abraham Clearfield
- 刊名：Chemistry of Materials
- 出版年：1999
- 出版时间：February 1999
- 年：1999
- 卷：11
- 期：2
- 页码：421 - 426
- 全文大小：110K
- 年卷期：v.11,no.2(February 1999)
- ISSN：1520-5002
文摘
The crystal structures of two new zinc compounds of propylenebis(phosphonic acid) weredetermined ab initio from their powder diffraction data. These compounds were preparedby the reaction of zinc chloride with the phosphonic acid at different pH conditions. Thecompound, Zn(HO3PC3H6PO3H) (1), crystallizes in the monoclinic space group P21/n with a= 18.167(3) Å, b = 5.083(1) Å, c = 8.658(1) Å, 
= 93.630(2)
and Z = 4. The other compound,Zn3[(HO3PC3H6PO3)2]·2H2O (2), also crystallizes in the monoclinic symmetry but with spacegroup C2/c. Crystal data: a = 20.5853(4) Å, b = 5.0472(1) Å, c = 18.0140(4) Å, b = 97.226(1),Z = 4. The intensities of the structure factors were extracted from the powder patternsusing the Le Bail method and were used for structure solution by direct methods. Thestructures were then completed by Fourier methods and refined by Rietveld methods. Instructure 1, the metal atoms are tetrahedrally coordinated by four oxygen atoms, two eachfrom two independent phosphonates. The remaining oxygen atom of both phosphonate groupsis protonated and is involved only in hydrogen bonding. The metal phosphonate interactionslead to double chains that are linked to each other through the organic linkages, leading totwo-dimensional slabs or sheets. These slabs are connected through hydrogen bonds, thusforming a loosely held three-dimensional metal phosphonate network. In the case ofcompound 2, only one of the phosphonate groups is protonated, while the other is completelydeprotonated. In this structure, there are two independent metal atoms that are tetrahedrallycoordinated. One is coordinated completely by phosphonate oxygen atoms, while thecoordination of the other zinc atom is by two phosphonate oxygens and two water oxygenatoms. The structure is interesting in that it consists of large one-dimensional pores whosedimensions are determined by the length of the organic moiety. Thus, this structure providesa starting point for a broad exploration of a new class of metal phosphonate porous materialswith varied pore sizes.
= 93.630(2) and Z = 4. The other compound,Zn3[(HO3PC3H6PO3)2]·2H2O (2), also crystallizes in the monoclinic symmetry but with spacegroup C2/c. Crystal data: a = 20.5853(4) Å, b = 5.0472(1) Å, c = 18.0140(4) Å, b = 97.226(1),Z = 4. The intensities of the structure factors were extracted from the powder patternsusing the Le Bail method and were used for structure solution by direct methods. Thestructures were then completed by Fourier methods and refined by Rietveld methods. Instructure 1, the metal atoms are tetrahedrally coordinated by four oxygen atoms, two eachfrom two independent phosphonates. The remaining oxygen atom of both phosphonate groupsis protonated and is involved only in hydrogen bonding. The metal phosphonate interactionslead to double chains that are linked to each other through the organic linkages, leading totwo-dimensional slabs or sheets. These slabs are connected through hydrogen bonds, thusforming a loosely held three-dimensional metal phosphonate network. In the case ofcompound 2, only one of the phosphonate groups is protonated, while the other is completelydeprotonated. In this structure, there are two independent metal atoms that are tetrahedrallycoordinated. One is coordinated completely by phosphonate oxygen atoms, while thecoordination of the other zinc atom is by two phosphonate oxygens and two water oxygenatoms. The structure is interesting in that it consists of large one-dimensional pores whosedimensions are determined by the length of the organic moiety. Thus, this structure providesa starting point for a broad exploration of a new class of metal phosphonate porous materialswith varied pore sizes.