| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 74573 | Microporous and Mesoporous Materials | 2012 | 6 Pages |
An open-framework manganese borophosphate (NH4)7Mn4(H2O)[B2P4O15(OH)2]2[H2PO4][HPO4] (1) has been synthesized by using 1-butyl-3-methyl-imidazolium bis(oxalato)borate ([C4mim][BOB]) ionic liquid as a boron source, and characterized by X-ray powder diffraction (XRD), inductively coupled plasma (ICP), element analysis, thermogravimetric analysis and differential scanning calorimetry (TG–DSC). Single-crystal X-ray diffraction analysis shows that compound 1 crystallizes in orthorhombic space group Pnma (No. 62), a = 17.102(2) Å, b = 10.7195(15) Å, c = 22.283(3) Å, V = 4085.0(10) Å3 and Z = 4. Its structure features an interrupted three-dimensional (3D) open-framework structure built up from [B2P4O15(OH)2]6− borophosphate anions, Mn2O10 dimers and HxPO43-x (x = 1, 2) groups, where peanut shaped extra-large 16-ring channels can be found extending along the [0 1 0] direction. Protonated NH3 molecules locate in the void space to balance the negative charges of the inorganic framework. Magnetic measurements indicate that antiferromagnetic interactions exist between Mn2+ ions with a negative Weiss constant of −18.2 K. The synthesis condition and various impact factors were studied carefully, which indicates that [BOB] anion of ionic liquid and acidity of the system are two important keys for the formation of the title compound.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A feasible route for new open-framework material preparation. ► A manganese borophosphate with extra-large 16-ring channels was synthesized. ► Chelated orthoborate ionic liquids were used as boron sources. ► Special boron-containing anion and acidity are two keys influencing the synthesis. ► Antiferromagnetic property.
