Journal article 823 views
Influence of π–π Stacking Interactions on the Assembly of Layered Copper Phosphonate Coordination Polymers: Combined Powder Diffraction and Electron Paramagnetic Resonance Study
M. Taddei,
F. Costantino,
R. Vivani,
C. Sangregorio,
L. Sorace,
L. Castelli,
Marco Taddei 
Crystal Growth & Design, Volume: 12, Issue: 5, Pages: 2327 - 2335
Swansea University Author:
Marco Taddei
Full text not available from this repository: check for access using links below.
DOI (Published version): 10.1021/cg201706p
Abstract
Three new copper phosphonate coordination polymers have been obtained following very soft synthetic routes, and their structures were determined ab initio from powder X-ray diffraction data. They are based on the two building blocks α,α′-m-xylylenediphosphonic and α,α′-p-xylylenediphosphonic acid, e...
| Published in: | Crystal Growth & Design |
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| ISSN: | 1528-7483 1528-7505 |
| Published: |
American Chemical Society (ACS)
2012
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| Online Access: |
Check full text
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| URI: | https://cronfa.swan.ac.uk/Record/cronfa32758 |
| Abstract: |
Three new copper phosphonate coordination polymers have been obtained following very soft synthetic routes, and their structures were determined ab initio from powder X-ray diffraction data. They are based on the two building blocks α,α′-m-xylylenediphosphonic and α,α′-p-xylylenediphosphonic acid, either exclusively or combined with 4,4′-bipyridine as an ancillary ligand. The compound obtained from α,α′-m-xylylenediphosphonate has the formula Cu(HO3PCH2)2C6H4·3H2O and a 2D structure of mixed organic–inorganic layers built up by the connection of inorganic chains made of edge-sharing copper octahedra via organic bridging groups. The compound obtained from α,α′-m-xylylenediphosphonate and 4,4′-bipyridine as a coligand has the formula Cu[(HO3PCH2)2C6H4][N(CH)4CC(CH)4N]·2H2O and a 2D structure based on the connection, via the diphosphonic ligand, of the linear chains resulting from the bridging of copper atoms by the bipyridine moieties. The compound obtained using α,α′-p-xylylenediphosphonate and 4,4′-bipyridine as a coligand has the same formula and a 2D structure closely resembling that of the previous compound. The influence of the factors driving the molecular assembly is discussed, pointing out the crucial role played by the 4,4′-bipyridine in promoting the π–π stacking interactions. With increasing temperatures, the compounds revealed a loss of water molecules bound to copper; in particular, heating the copper α,α′-m-xylylenediphosphonate–bipyridine results in a relatively stable phase with unsaturated coordination sites on the metal atoms. This behavior was confirmed by magnetic susceptibility and electron paramagnetic resonance measurements which also provided evidence for a partial reversibility of the dehydration process and of the occurrence of weak antiferromagnetic interactions between Cu(II) ions. |
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| College: |
Faculty of Science and Engineering |
| Issue: |
5 |
| Start Page: |
2327 |
| End Page: |
2335 |