Formation of Ho-III Trinuclear Clusters and Gd-III Monodimensional Polymers Induced by ortho and para Regioisomers of Pyridyl-Functionalised beta-Diketones: Synthesis, Structure, and Magnetic Properties
Reaction of GdCl3(H2O)(6) and 1,3-bis(pyridin-4-yl)propane-1,3-dione in methanol with an excess of triethylamine produced a monodimensional polymeric chain [Gd(p-dppd)(3)-(H2O)](infinity), whereas treatment of HoCl3(H2O)(6) with 1,3-bis(pyridin-2-yl)propane-1,3-dione yielded a trinuclear cluster [Ho...
| Main Authors: | , , , , , , , , , |
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| Format: | Journal Article |
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Wiley-VCH Verlag GmbH & Co
2009
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| Online Access: | http://hdl.handle.net/20.500.11937/42842 |
| _version_ | 1848756529628446720 |
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| author | Andrews, P. Deacon, G. Frank, R. Fraser, B. Junk, P. Maclellan, J. Massi, Massimiliano Moubaraki, B. Murray, K. Silberstein, Morry |
| author_facet | Andrews, P. Deacon, G. Frank, R. Fraser, B. Junk, P. Maclellan, J. Massi, Massimiliano Moubaraki, B. Murray, K. Silberstein, Morry |
| author_sort | Andrews, P. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Reaction of GdCl3(H2O)(6) and 1,3-bis(pyridin-4-yl)propane-1,3-dione in methanol with an excess of triethylamine produced a monodimensional polymeric chain [Gd(p-dppd)(3)-(H2O)](infinity), whereas treatment of HoCl3(H2O)(6) with 1,3-bis(pyridin-2-yl)propane-1,3-dione yielded a trinuclear cluster [Ho-3(o-dppd)(3)(mu(3)-OH)(2)(H2O)(4)Cl-2]Cl-2. The compounds were characterised by elemental analysis, IR spectroscopy and magnetism, and their structures were investigated by X-ray crystallography. The 8.20-mu(B) magnetic-moment value of the polymeric [Gd(p-dppd)(3)(H2O)](infinity), between 300 and 20 K, and the magnetisation isotherms (2-20 K; fields 0-5 T), are in agreement with essentially uncoupled single-ion Gd3+ f(7) centres, a small decrease in mu(eff) below 20 K being indicative of zero-field splitting. A temperature-dependent dc-susceptibility and magnetisation investigation of the trinuclear (tri-angular) [Ho-3(o-dppd)(3)(mu(3)-OH)(2)(H2O)(4)Cl-2]Cl-2 revealed that spin-orbit and ligand-field effects on the Ho3+ centres, leading to thermal depopulation of Zeeman levels and consequent decreases in mu(eff) values with decreasing temperature, are occurring rather than weak intra-cluster antiferromagnetic coupling. Frequency- and temperature-dependent ac-susceptibility studies on this homometallic Ho3+ cluster did not show clear evidence for slow magnetisation reversal, characteristic of single-molecule magnetism (SMM), and this contrasts with such behaviour recently reported, elsewhere, for a Dy3+ triangle having the same core structure but with different chelating {O,O} ligands. |
| first_indexed | 2025-11-14T09:13:39Z |
| format | Journal Article |
| id | curtin-20.500.11937-42842 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T09:13:39Z |
| publishDate | 2009 |
| publisher | Wiley-VCH Verlag GmbH & Co |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-428422017-02-28T01:45:42Z Formation of Ho-III Trinuclear Clusters and Gd-III Monodimensional Polymers Induced by ortho and para Regioisomers of Pyridyl-Functionalised beta-Diketones: Synthesis, Structure, and Magnetic Properties Andrews, P. Deacon, G. Frank, R. Fraser, B. Junk, P. Maclellan, J. Massi, Massimiliano Moubaraki, B. Murray, K. Silberstein, Morry LINKERS LIGANDS LANTHANIDE CLUSTERS N COORDINATION POLYMERS CUBANE CLUSTERS Coordination polymers O ligands DYSPROSIUM TRIANGLES Cluster compounds SURFACE Ketones CHEMISTRY beta-Diketonate ligands Molecular magnets Chelates TETRANUCLEAR COMPLEXES Reaction of GdCl3(H2O)(6) and 1,3-bis(pyridin-4-yl)propane-1,3-dione in methanol with an excess of triethylamine produced a monodimensional polymeric chain [Gd(p-dppd)(3)-(H2O)](infinity), whereas treatment of HoCl3(H2O)(6) with 1,3-bis(pyridin-2-yl)propane-1,3-dione yielded a trinuclear cluster [Ho-3(o-dppd)(3)(mu(3)-OH)(2)(H2O)(4)Cl-2]Cl-2. The compounds were characterised by elemental analysis, IR spectroscopy and magnetism, and their structures were investigated by X-ray crystallography. The 8.20-mu(B) magnetic-moment value of the polymeric [Gd(p-dppd)(3)(H2O)](infinity), between 300 and 20 K, and the magnetisation isotherms (2-20 K; fields 0-5 T), are in agreement with essentially uncoupled single-ion Gd3+ f(7) centres, a small decrease in mu(eff) below 20 K being indicative of zero-field splitting. A temperature-dependent dc-susceptibility and magnetisation investigation of the trinuclear (tri-angular) [Ho-3(o-dppd)(3)(mu(3)-OH)(2)(H2O)(4)Cl-2]Cl-2 revealed that spin-orbit and ligand-field effects on the Ho3+ centres, leading to thermal depopulation of Zeeman levels and consequent decreases in mu(eff) values with decreasing temperature, are occurring rather than weak intra-cluster antiferromagnetic coupling. Frequency- and temperature-dependent ac-susceptibility studies on this homometallic Ho3+ cluster did not show clear evidence for slow magnetisation reversal, characteristic of single-molecule magnetism (SMM), and this contrasts with such behaviour recently reported, elsewhere, for a Dy3+ triangle having the same core structure but with different chelating {O,O} ligands. 2009 Journal Article http://hdl.handle.net/20.500.11937/42842 Wiley-VCH Verlag GmbH & Co restricted |
| spellingShingle | LINKERS LIGANDS LANTHANIDE CLUSTERS N COORDINATION POLYMERS CUBANE CLUSTERS Coordination polymers O ligands DYSPROSIUM TRIANGLES Cluster compounds SURFACE Ketones CHEMISTRY beta-Diketonate ligands Molecular magnets Chelates TETRANUCLEAR COMPLEXES Andrews, P. Deacon, G. Frank, R. Fraser, B. Junk, P. Maclellan, J. Massi, Massimiliano Moubaraki, B. Murray, K. Silberstein, Morry Formation of Ho-III Trinuclear Clusters and Gd-III Monodimensional Polymers Induced by ortho and para Regioisomers of Pyridyl-Functionalised beta-Diketones: Synthesis, Structure, and Magnetic Properties |
| title | Formation of Ho-III Trinuclear Clusters and Gd-III Monodimensional Polymers Induced by ortho and para Regioisomers of Pyridyl-Functionalised beta-Diketones: Synthesis, Structure, and Magnetic Properties |
| title_full | Formation of Ho-III Trinuclear Clusters and Gd-III Monodimensional Polymers Induced by ortho and para Regioisomers of Pyridyl-Functionalised beta-Diketones: Synthesis, Structure, and Magnetic Properties |
| title_fullStr | Formation of Ho-III Trinuclear Clusters and Gd-III Monodimensional Polymers Induced by ortho and para Regioisomers of Pyridyl-Functionalised beta-Diketones: Synthesis, Structure, and Magnetic Properties |
| title_full_unstemmed | Formation of Ho-III Trinuclear Clusters and Gd-III Monodimensional Polymers Induced by ortho and para Regioisomers of Pyridyl-Functionalised beta-Diketones: Synthesis, Structure, and Magnetic Properties |
| title_short | Formation of Ho-III Trinuclear Clusters and Gd-III Monodimensional Polymers Induced by ortho and para Regioisomers of Pyridyl-Functionalised beta-Diketones: Synthesis, Structure, and Magnetic Properties |
| title_sort | formation of ho-iii trinuclear clusters and gd-iii monodimensional polymers induced by ortho and para regioisomers of pyridyl-functionalised beta-diketones: synthesis, structure, and magnetic properties |
| topic | LINKERS LIGANDS LANTHANIDE CLUSTERS N COORDINATION POLYMERS CUBANE CLUSTERS Coordination polymers O ligands DYSPROSIUM TRIANGLES Cluster compounds SURFACE Ketones CHEMISTRY beta-Diketonate ligands Molecular magnets Chelates TETRANUCLEAR COMPLEXES |
| url | http://hdl.handle.net/20.500.11937/42842 |