Alkaline-Earth (Mg-Ba) Coordination Networks Built Around the Tris(dipicolinato)cerate(3(-)) Ion: Highly Hydrated Networks That Survive Dehydration

作者：Elahi S M; Rajasekharan M V^*

来源：European Journal of Inorganic Chemistry, 2015, 2015(1): 171-178.

DOI：10.1002/ejic.201402591

• Cerium
• Alkaline earth metals
• Coordination modes
• Microporous materials

Alkaline-earth (AE)/cerium(III)-based heterometallic coordination compounds of the biologically important ligand dipicolinic acid (dipicH(2)), namely [Mg(H2O)(6)](2)[Ce(dipic)(3)][Ce(dipic)(2)(H2O)(3)]2H(2)O (1), [Ca-3(H2O)(12)Ce-2(dipic)(6)]6H(2)O (2), [Sr-3(H2O)(16)Ce-2(dipic)(6)]4H(2)O (3) and [Ba-2(H2O)(7)Ce(dipic)(3)NO3]H2O (4), have been obtained by the reduction of an aqueous solution of (NH4)(2)Ce(NO3)(6)6H(2)O in the presence of dipicH(2) and alkaline-earth oxides or carbonates. This series demonstrates the role of AE ions in controlling the topology of coordination networks based on the [Ce(dipic)(3)](3-) anion. Compound 1 is a zero-dimensional ionic compound, the crystal structure of compound 2 is based on a mixed four-connected 3D network, compound 3 presents ladder-shaped chains running along a crystallographic axis, and layers of squeezed CeBa6 pentagonal pyramids interconnected by nitrates generate a mixed five- and six-connected network in 4. A thermal analysis showed that all four compounds exhibit reversible water-uptake capacity and the basic nature of the frameworks could be intact up to at least 120 degrees C.

• 出版日期2015-1