0000000001298904
AUTHOR
Verónica Jornet-mollá
Interplay between spin crossover and proton migration along short strong hydrogen bonds
The iron(ii) salt [Fe(bpp)2](isonicNO)2·HisonicNO·5H2O (1) (bpp = 2,6-bis(pyrazol-3-yl)pyridine; isonicNO = isonicotinate N-oxide anion) undergoes a partial spin crossover (SCO) with symmetry breaking at T1 = 167 K to a mixed-spin phase (50% high-spin (HS), 50% low-spin (LS)) that is metastable below T2 = 116 K. Annealing the compound at lower temperatures results in a 100% LS phase that differs from the initial HS phase in the formation of a hydrogen bond (HB) between two water molecules (O4W and O5W) of crystallisation. Neutron crystallography experiments have also evidenced a proton displacement inside a short strong hydrogen bond (SSHB) between two isonicNO anions. Both phenomena can al…
Synthesis of rigid ethynyl-bridged polytopic picolinate ligands for MOF applications
Abstract Segmented homopolytopic ligands that consist of a rigid central arylene platform, ethynylene spacers, and terminal chelating picolinate subunits have been synthesized in good yields in a two-step procedure involving a Sonogashira-type cross coupling reaction between the ester methyl 5-bromopyridine-2-carboxylate and several arylacetylenes, followed by hydrolysis of the resulting methyl picolinates. A similar strategy has been employed for the preparation of heteroditopic ligands containing picolinate and a second non-chelating pyridine or benzoate unit. The compounds are potential candidates for organic linkers in metal–organic frameworks (MOFs).
A reversible hydrogen‐bond isomerization triggered by an abrupt spin crossover near room temperature.
The spin crossover salt [Fe(bpp) 2 ](isonicNO) 2 ·2.4H 2 O ( 1 ·2.4H 2 O) (bpp = 2,6‐bis(pyrazol‐3‐yl)pyridine; isonicNO = isonicotinate N‐oxide anion) exhibits a very abrupt spin crossover at T 1 /2 = 274.4 K. This triggers a supramolecular linkage (H‐bond) isomerization that responds reversibly towards light irradiation or temperature change. Isotopic effects in the thermomagnetic behaviour reveal the importance of hydrogen bonds in defining the magnetic state. Further, the title compound can be reversibly dehydrated to afford 1 , a material that also exhibits spin crossover coupled to H‐bond isomerization, leading to strong kinetic effects in the thermomagnetic properties.
Hydrogen-bonded networks of [Fe(bpp)2]2+spin crossover complexes and dicarboxylate anions: structural and photomagnetic properties
The paper reports the syntheses, crystal structures, thermal and (photo)magnetic properties of spin crossover salts of formula [Fe(bpp)2](C6H8O4)·4H2O (1·4H2O), [Fe(bpp)2](C8H4O4)·2CH3OH·H2O (2·2MeOH·H2O) and [Fe(bpp)2](C8H4O4)·5H2O (2·5H2O) (bpp = 2,6-bis(pyrazol-3yl)pyridine; C6H8O4 = adipate dianion; C8H4O4 = terephthalate dianion). The salts exhibit an intricate network of hydrogen bonds between low-spin iron(II) complexes and carboxylate dianions, with solvent molecules sitting in the voids. Desolvation is accompanied by a low-spin (LS) to high-spin (HS) transformation in the materials. The dehydrated phase 2 undergoes a two-step transition with a second step showing thermal hysteresis…
A Ferroelectric Iron(II) Spin Crossover Material
A dual-function material in which ferroelectricity and spin crossover coexist in the same temperature range has been obtained. Our synthetic strategy allows the construction of acentric crystal structures in a predictable way and is based on the high directionality of hydrogen bonds. The well-known iron(II) spin crossover complex [Fe(bpp)₂]²+ (bpp = 2,6-bis(pyrazol-3-yl)pyridine), a four-fold noncentrosymmetric H-bond donor, was combined with a disymmetric H-bond acceptor such as the isonicotinate (isonic) anion to afford [Fe(bpp)₂](isonic)₂·2H₂O. This low-spin iron(II) compound crystallises in the acentric nonpolar I-4 space group and shows piezoelectricity and SHG properties. Upon dehydra…
Temperature dependence of desolvation effects in hydrogen-bonded spin crossover complexes
The synthesis, crystal structure and (photo)magnetic properties of the anhydrous spin crossover salt of formula [Fe(bpp)2](C6H8O4) (1) (bpp = 2,6-bis(pyrazol-3-yl)pyridine; C6H8O4 = adipate dianion), obtained by desolvation at 400 K of the original tetrahydrate in a single-crystal-to-single-crystal (SC–SC) transformation, are reported. This work offers a comparison between this compound and the previously reported hydrated material ([Fe(bpp)2](C6H8O4)·4H2O, 1·4H2O), highlighting the significance of the thermal conditions used in the dehydration-rehydration processes. In both compounds, a hydrogen-bonded network between iron(II) complexes and adipate anions is observed. The original tetrahyd…
Synthesis, crystal structures and magnetic properties of picolinate-bridged copper(II) chains
The paper reports the synthesis, crystal structures, and magnetic properties of two copper(II) coordination polymers, Cu2(L1)4 (1) and Cu3(L2)6 (2), based on rigid ethynylene-bridged ditopic ligands containing one picolinate subunit (L1 = 5-(pyridin-3-ylethynyl)picolinate anion; L2 = 5-((4-(methoxycarbonyl)phenyl)ethynyl)picolinate anion). Both 1 and 2 have a chain structure. In 1, the repeating unit in the chain is a doubly bridged picolinate dicopper(II) complex, whereas 2 is built upon trimeric units where the Cu2+ ions are also connected by double picolinate bridges. Both compounds exhibit antiferromagnetic interactions in the solid state. The magnetic properties of 1 and 2 were analyze…
Robust Lanthanoid Picolinate-Based Coordination Polymers for Luminescence and Sensing Applications
Picolinate-based segmented dianionic ligands L12– (5-((4-carboxyphenyl)ethynyl)picolinate) and L22– (5,5′-(ethyne-1,2-diyl)dipicolinate) have been used in the synthesis of the highly robust and luminescent europium(III) coordination polymers [(CH3)2NH2][Eu(H2O)2(L1)2] (1) and [(CH3)2NH2][Eu(L2)2]·H2O·CH3COOH (2). Both 1 and 2 exhibit high selectivity for detection of nitroaromatic compounds since they act as quenchers of the Eu3+ emission. Stern–Volmer plots, using nitrobenzene as a quencher, yielded values of KSV = 150 M–1 and 160 M–1 for 1 and 2, respectively. Luminescence studies in the presence of different metal ions indicate a high selectivity for Fe3+ detection, with KSV values of 47…
CCDC 1984964: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Laura Cañadillas-Delgado, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2021|Chemical Science|12|1038|doi:10.1039/D0SC04918B
CCDC 1577301: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Martín-Mezquita, Yan Duan, Carlos Giménez-Saiz, Francisco M. Romero|2018|J.Coord.Chem.|71|644|doi:10.1080/00958972.2018.1437267
CCDC 1984962: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Laura Cañadillas-Delgado, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2021|Chemical Science|12|1038|doi:10.1039/D0SC04918B
CCDC 1491308: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Yan Duan, Carlos Giménez-Saiz, João C. Waerenborgh, Francisco M. Romero|2016|Dalton Trans.|45|17918|doi:10.1039/C6DT02934E
CCDC 1555238: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Yan Duan, Carlos Gimenez-Saiz, Yuan-Yuan Tang, Peng-Fei Li, Francisco M. Romero, Ren-Gen Xiong|2017|Angew.Chem.,Int.Ed.|56|14052|doi:10.1002/anie.201707401
CCDC 1973926: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2020|Chem.-Eur.J.|27|740|doi:10.1002/chem.202003654
CCDC 1973938: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2020|Chem.-Eur.J.|27|740|doi:10.1002/chem.202003654
CCDC 1491307: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Yan Duan, Carlos Giménez-Saiz, João C. Waerenborgh, Francisco M. Romero|2016|Dalton Trans.|45|17918|doi:10.1039/C6DT02934E
CCDC 1984958: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Laura Cañadillas-Delgado, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2021|Chemical Science|12|1038|doi:10.1039/D0SC04918B
CCDC 2013419: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2020|Chem.-Eur.J.|27|740|doi:10.1002/chem.202003654
CCDC 1973924: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2020|Chem.-Eur.J.|27|740|doi:10.1002/chem.202003654
CCDC 1973940: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2020|Chem.-Eur.J.|27|740|doi:10.1002/chem.202003654
CCDC 1984961: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Laura Cañadillas-Delgado, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2021|Chemical Science|12|1038|doi:10.1039/D0SC04918B
CCDC 1973936: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2020|Chem.-Eur.J.|27|740|doi:10.1002/chem.202003654
CCDC 1832988: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Laura Cañadillas-Delgado, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2021|Chemical Science|12|1038|doi:10.1039/D0SC04918B
CCDC 1577302: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Yan Duan, Carlos Gimenez-Saiz, Yuan-Yuan Tang, Peng-Fei Li, Francisco M. Romero, Ren-Gen Xiong|2017|Angew.Chem.,Int.Ed.|56|14052|doi:10.1002/anie.201707401
CCDC 1973941: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2020|Chem.-Eur.J.|27|740|doi:10.1002/chem.202003654
CCDC 1984957: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Laura Cañadillas-Delgado, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2021|Chemical Science|12|1038|doi:10.1039/D0SC04918B
CCDC 1507864: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Bruno J. C. Vieira, João C. Waerenborgh, Francisco M. Romero|2021|Dalton Trans.|50|2536|doi:10.1039/D0DT03986A
CCDC 1974500: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2020|Chem.-Eur.J.|27|740|doi:10.1002/chem.202003654
CCDC 1491309: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Yan Duan, Carlos Giménez-Saiz, João C. Waerenborgh, Francisco M. Romero|2016|Dalton Trans.|45|17918|doi:10.1039/C6DT02934E
CCDC 1832962: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Laura Cañadillas-Delgado, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2021|Chemical Science|12|1038|doi:10.1039/D0SC04918B
CCDC 1984960: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Laura Cañadillas-Delgado, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2021|Chemical Science|12|1038|doi:10.1039/D0SC04918B
CCDC 1973928: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2020|Chem.-Eur.J.|27|740|doi:10.1002/chem.202003654
CCDC 1819792: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Bruno J. C. Vieira, João C. Waerenborgh, Francisco M. Romero|2021|Dalton Trans.|50|2536|doi:10.1039/D0DT03986A
CCDC 1577300: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Martín-Mezquita, Yan Duan, Carlos Giménez-Saiz, Francisco M. Romero|2018|J.Coord.Chem.|71|644|doi:10.1080/00958972.2018.1437267
CCDC 1984963: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Laura Cañadillas-Delgado, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2021|Chemical Science|12|1038|doi:10.1039/D0SC04918B
CCDC 1973929: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2020|Chem.-Eur.J.|27|740|doi:10.1002/chem.202003654
CCDC 1554603: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Yan Duan, Carlos Gimenez-Saiz, Yuan-Yuan Tang, Peng-Fei Li, Francisco M. Romero, Ren-Gen Xiong|2017|Angew.Chem.,Int.Ed.|56|14052|doi:10.1002/anie.201707401
CCDC 1554602: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Yan Duan, Carlos Gimenez-Saiz, Yuan-Yuan Tang, Peng-Fei Li, Francisco M. Romero, Ren-Gen Xiong|2017|Angew.Chem.,Int.Ed.|56|14052|doi:10.1002/anie.201707401
CCDC 1984959: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Laura Cañadillas-Delgado, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2021|Chemical Science|12|1038|doi:10.1039/D0SC04918B
CCDC 1873604: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Laura Cañadillas-Delgado, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2021|Chemical Science|12|1038|doi:10.1039/D0SC04918B
CCDC 1873602: Experimental Crystal Structure Determination
Related Article: Verónica Jornet-Mollá, Carlos Giménez-Saiz, Laura Cañadillas-Delgado, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero|2021|Chemical Science|12|1038|doi:10.1039/D0SC04918B