Closely-related ZnII2LnIII 2 complexes (LnIII = Gd, Yb) with either magnetic refrigerant or luminescent single-molecule magnet properties
The reaction of the compartmental ligand N,N′,N″-trimethyl-N,N″-bis(2-hydroxy-3-methoxy-5-methylbenzyl)diethylenetriamine (H2L) with Zn(NO3)2·6H2O and subsequently with Ln(NO3)3·5H2O (LnIII = Gd and Yb) and triethylamine in MeOH using a 1:1:1:1 molar ratio leads to the formation of the tetranuclear...
| Autores: | , , , , , , |
|---|---|
| Tipo de recurso: | artículo |
| Estado: | Versión aceptada para publicación |
| Fecha de publicación: | 2014 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/117972 |
| Acceso en línea: | http://hdl.handle.net/10261/117972 |
| Access Level: | acceso abierto |
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| dc.title.none.fl_str_mv |
Closely-related ZnII2LnIII 2 complexes (LnIII = Gd, Yb) with either magnetic refrigerant or luminescent single-molecule magnet properties |
| title |
Closely-related ZnII2LnIII 2 complexes (LnIII = Gd, Yb) with either magnetic refrigerant or luminescent single-molecule magnet properties |
| spellingShingle |
Closely-related ZnII2LnIII 2 complexes (LnIII = Gd, Yb) with either magnetic refrigerant or luminescent single-molecule magnet properties Ruiz, José |
| title_short |
Closely-related ZnII2LnIII 2 complexes (LnIII = Gd, Yb) with either magnetic refrigerant or luminescent single-molecule magnet properties |
| title_full |
Closely-related ZnII2LnIII 2 complexes (LnIII = Gd, Yb) with either magnetic refrigerant or luminescent single-molecule magnet properties |
| title_fullStr |
Closely-related ZnII2LnIII 2 complexes (LnIII = Gd, Yb) with either magnetic refrigerant or luminescent single-molecule magnet properties |
| title_full_unstemmed |
Closely-related ZnII2LnIII 2 complexes (LnIII = Gd, Yb) with either magnetic refrigerant or luminescent single-molecule magnet properties |
| title_sort |
Closely-related ZnII2LnIII 2 complexes (LnIII = Gd, Yb) with either magnetic refrigerant or luminescent single-molecule magnet properties |
| dc.creator.none.fl_str_mv |
Ruiz, José Lorusso, Giulia Evangelisti, Marco Herrera, Juan Manuel Brechin, Euan K. Pope, Simon J. A. Colacio, Enrique |
| author |
Ruiz, José |
| author_facet |
Ruiz, José Lorusso, Giulia Evangelisti, Marco Herrera, Juan Manuel Brechin, Euan K. Pope, Simon J. A. Colacio, Enrique |
| author_role |
author |
| author2 |
Lorusso, Giulia Evangelisti, Marco Herrera, Juan Manuel Brechin, Euan K. Pope, Simon J. A. Colacio, Enrique |
| author2_role |
author author author author author author |
| dc.contributor.none.fl_str_mv |
European Commission Ministerio de Economía y Competitividad (España) Junta de Andalucía Universidad de Granada Engineering and Physical Sciences Research Council (UK) Cardiff University Consejo Superior de Investigaciones Científicas [https://ror.org/02gfc7t72] |
| description |
The reaction of the compartmental ligand N,N′,N″-trimethyl-N,N″-bis(2-hydroxy-3-methoxy-5-methylbenzyl)diethylenetriamine (H2L) with Zn(NO3)2·6H2O and subsequently with Ln(NO3)3·5H2O (LnIII = Gd and Yb) and triethylamine in MeOH using a 1:1:1:1 molar ratio leads to the formation of the tetranuclear complexes {(μ3-CO3)2[Zn(μ-L)Gd(NO3)]2}·4CH3OH (1) and{(μ3-CO3)2[Zn(μ-L)Yb(H2O)]2}(NO3)2·4CH3OH (2). When the reaction was performed in the absence of triethylamine, the dinuclear compound [Zn(μ-L)(μ-NO3)Yb(NO3)2] (3) is obtained. The structures of 1 and 2 consist of two diphenoxo-bridged ZnII–LnIII units connected by two carbonate bridging ligands. Within the dinuclear units, ZnII and LnIII ions occupy the N3O2 inner and the O4 outer sites of the compartmental ligand, respectively. The remaining positions on the LnIII ions are occupied by oxygen atoms belonging to the carbonate bridging groups, by a bidentate nitrate ion in 1, and by a coordinated water molecule in 2, leading to rather asymmetric GdO9 and trigonal dodecahedron YbO8 coordination spheres, respectively. Complex 3 is made of acetate–diphenoxo triply bridged ZnIIYbIII dinuclear units, where the YbIII exhibits a YbO9 coordination environment. Variable-temperature magnetization measurements and heat capacity data demonstrate that 1 has a significant magneto–caloric effect, with a maximum value of −ΔSm = 18.5 J kg–1 K–1 at T = 1.9 K and B = 7 T. Complexes 2 and 3 show slow relaxation of the magnetization and single-molecule magnet (SMM) behavior under an applied direct-current field of 1000 Oe. The fit of the high-temperature data to the Arrhenius equation affords an effective energy barrier for the reversal of the magnetization of 19.4(7) K with τo = 3.1 × 10–6 s and 27.0(9) K with τo = 8.8 × 10–7 s for 2 and 3, respectively. However, the fit of the full range of temperature data indicates that the relaxation process could take place through a Raman-like process rather than through an activated Orbach process. The chromophoric L2– ligand is able to act as an “antenna” group, sensitizing the near-infrared (NIR) YbIII-based luminescence in complexes 2 and 3 through an intramolecular energy transfer to the excited states of the accepting YbIII ion. These complexes show several bands in the 945–1050 nm region, corresponding to 2F5/2→2F7/2 transitions arising from the ligand field splitting of both multiplets. The observed luminescence lifetimes τobs are 0.515 and 10 μs for 2 and 3, respectively. The shorter lifetime for 2 is due to the presence of one coordinated water molecule on the YbIII center (and to a lesser extent noncoordinated water molecules), facilitating vibrational quenching via O–H oscillators. Therefore, complexes 2 and 3, combining field-induced SMM behavior. |
| publishDate |
2014 |
| dc.date.none.fl_str_mv |
2014 2015 2015 2015 |
| dc.type.none.fl_str_mv |
info:eu-repo/semantics/article http://purl.org/coar/resource_type/c_6501 Postprint info:eu-repo/semantics/acceptedVersion |
| format |
article |
| status_str |
acceptedVersion |
| dc.identifier.none.fl_str_mv |
http://hdl.handle.net/10261/117972 |
| url |
http://hdl.handle.net/10261/117972 |
| dc.language.none.fl_str_mv |
Inglés |
| language_invalid_str_mv |
Inglés |
| dc.relation.none.fl_str_mv |
#PLACEHOLDER_PARENT_METADATA_VALUE# info:eu-repo/grantAgreement/EC/FP7/299356 http://dx.doi.org/10.1021/ic403097s Sí |
| dc.rights.none.fl_str_mv |
info:eu-repo/semantics/openAccess |
| eu_rights_str_mv |
openAccess |
| dc.publisher.none.fl_str_mv |
American Chemical Society |
| publisher.none.fl_str_mv |
American Chemical Society |
| dc.source.none.fl_str_mv |
reponame:DIGITAL.CSIC. Repositorio Institucional del CSIC instname:Consejo Superior de Investigaciones Científicas (CSIC) |
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Consejo Superior de Investigaciones Científicas (CSIC) |
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DIGITAL.CSIC. Repositorio Institucional del CSIC |
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DIGITAL.CSIC. Repositorio Institucional del CSIC |
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| _version_ |
1869410777140559872 |
| spelling |
Closely-related ZnII2LnIII 2 complexes (LnIII = Gd, Yb) with either magnetic refrigerant or luminescent single-molecule magnet propertiesRuiz, JoséLorusso, GiuliaEvangelisti, MarcoHerrera, Juan ManuelBrechin, Euan K.Pope, Simon J. A.Colacio, EnriqueThe reaction of the compartmental ligand N,N′,N″-trimethyl-N,N″-bis(2-hydroxy-3-methoxy-5-methylbenzyl)diethylenetriamine (H2L) with Zn(NO3)2·6H2O and subsequently with Ln(NO3)3·5H2O (LnIII = Gd and Yb) and triethylamine in MeOH using a 1:1:1:1 molar ratio leads to the formation of the tetranuclear complexes {(μ3-CO3)2[Zn(μ-L)Gd(NO3)]2}·4CH3OH (1) and{(μ3-CO3)2[Zn(μ-L)Yb(H2O)]2}(NO3)2·4CH3OH (2). When the reaction was performed in the absence of triethylamine, the dinuclear compound [Zn(μ-L)(μ-NO3)Yb(NO3)2] (3) is obtained. The structures of 1 and 2 consist of two diphenoxo-bridged ZnII–LnIII units connected by two carbonate bridging ligands. Within the dinuclear units, ZnII and LnIII ions occupy the N3O2 inner and the O4 outer sites of the compartmental ligand, respectively. The remaining positions on the LnIII ions are occupied by oxygen atoms belonging to the carbonate bridging groups, by a bidentate nitrate ion in 1, and by a coordinated water molecule in 2, leading to rather asymmetric GdO9 and trigonal dodecahedron YbO8 coordination spheres, respectively. Complex 3 is made of acetate–diphenoxo triply bridged ZnIIYbIII dinuclear units, where the YbIII exhibits a YbO9 coordination environment. Variable-temperature magnetization measurements and heat capacity data demonstrate that 1 has a significant magneto–caloric effect, with a maximum value of −ΔSm = 18.5 J kg–1 K–1 at T = 1.9 K and B = 7 T. Complexes 2 and 3 show slow relaxation of the magnetization and single-molecule magnet (SMM) behavior under an applied direct-current field of 1000 Oe. The fit of the high-temperature data to the Arrhenius equation affords an effective energy barrier for the reversal of the magnetization of 19.4(7) K with τo = 3.1 × 10–6 s and 27.0(9) K with τo = 8.8 × 10–7 s for 2 and 3, respectively. However, the fit of the full range of temperature data indicates that the relaxation process could take place through a Raman-like process rather than through an activated Orbach process. The chromophoric L2– ligand is able to act as an “antenna” group, sensitizing the near-infrared (NIR) YbIII-based luminescence in complexes 2 and 3 through an intramolecular energy transfer to the excited states of the accepting YbIII ion. These complexes show several bands in the 945–1050 nm region, corresponding to 2F5/2→2F7/2 transitions arising from the ligand field splitting of both multiplets. The observed luminescence lifetimes τobs are 0.515 and 10 μs for 2 and 3, respectively. The shorter lifetime for 2 is due to the presence of one coordinated water molecule on the YbIII center (and to a lesser extent noncoordinated water molecules), facilitating vibrational quenching via O–H oscillators. Therefore, complexes 2 and 3, combining field-induced SMM behavior.Financial support from Ministerio de Economíay Competitividad (MINECO) for Projects CTQ-2011-24478 and MAT2012-38318-C03-01, the Junta de Andalucía (FQM-195 and the Project of Excellence P11-FQM-7756), and the University of Granada is acknowledged. E.K.B. thanks the EPSRC for funding. S.J.A.P. thanks Cardiff University and the EPSRC. G.L. acknowledges EU for a Marie Curie IEF (PIEFGA- 2011-299356).Peer ReviewedAmerican Chemical SocietyEuropean CommissionMinisterio de Economía y Competitividad (España)Junta de AndalucíaUniversidad de GranadaEngineering and Physical Sciences Research Council (UK)Cardiff UniversityConsejo Superior de Investigaciones Científicas [https://ror.org/02gfc7t72]2015201520142015info:eu-repo/semantics/articlehttp://purl.org/coar/resource_type/c_6501Postprintinfo:eu-repo/semantics/acceptedVersionhttp://hdl.handle.net/10261/117972reponame:DIGITAL.CSIC. Repositorio Institucional del CSICinstname:Consejo Superior de Investigaciones Científicas (CSIC)Inglés#PLACEHOLDER_PARENT_METADATA_VALUE#info:eu-repo/grantAgreement/EC/FP7/299356http://dx.doi.org/10.1021/ic403097sSíinfo:eu-repo/semantics/openAccessoai:digital.csic.es:10261/1179722026-05-22T06:33:51Z |
| score |
15,812429 |