A Novel Three-Dimensional Copper(II) 1,2-Ethylenediphosphonate Framework with Channel-like Voids

作者：Koeferstein Roberto; Arnold Michael; Robl Christian^*

来源：Zeitschrift fur Anorganische und Allgemeine Chemie, 2016, 642(19): 1126-1132.

DOI：10.1002/zaac.201600248

• 1,2-Ethylenediphosphonic acid
• Metal-organic framework
• Crystal structure
• Channel-like voids
• Magnetic properties
• UV/Vis spectroscopy

Turquoise monoclinic single crystals of the novel three-dimensional Cu-2[mu(8)-O3P(CH2)(2)PO3]center dot 3.2H(2)O coordination polymer were prepared using the silica gel method. Space group C2/m (no. 12) with a = 1483.6(2), b = 668.44(8), c = 436.30(6) pm, beta = 93.28(2)degrees. The Cu2+ cation is coordinated by four oxygen atoms stemming from the 1,2-ethylenediphosphonate dianions in a square planar manner and two water molecules in the axial positions. The connection between the Cu2+ cations and the [CPO3] units from the 1,2-ethylenediphosphonate dianions leads to layers parallel to (100), which are linked by the ethylene groups to a three-dimensional framework with channel-like voids. The channel-like voids accommodate water molecules not bound to Cu2+ and extend parallel to [001] with an opening of about 550 pm x 260 pm. Magnetic measurements reveal an anti-ferromagnetic behavior due to a superexchange coupling between Cu2+ ions through an oxygen bridge. The UV/Vis spectrum reveals three d-d transition bands at 694, 774, and 918 nm. The compound can be fully dehydrated by thermal treatment and rehydrated by storage in ambient air.

• 出版日期2016-9