TY - JOUR
T1 - Structural and magnetic modulation of a purely organic open framework by selective guest inclusion
AU - Maspoch, Daniel
AU - Domingo, Neus
AU - Roques, Nans
AU - Wurst, Klaus
AU - Tejada, Javier
AU - Rovira, Concepció
AU - Ruiz-Molina, Daniel
AU - Veciana, Jaume
PY - 2007
Y1 - 2007
N2 - Solvent inclusion/evacuation caused variations in the structural and magnetic characteristics of the purely organic porous magnet based on the tricarboxylic-substituted PTMTC radical. Whereas no inclusion is observed for nonpolar solvents, the exposure of crystals of the α-phase of PTMTC to vapors of polar organic solvents with hydrogen acceptor and/or donor functionalities, such as, ethanol, benzoic alcohol, n-decanol, THF, and DMSO results in the inclusion of these solvents in the highly polar tubular channels of the α-phase. The resulting inclusion compounds of formula PTMTC. x(guest) show several structural rearrangements, as confirmed by IR and XRPD (X-ray powder diffraction) measurements. The crystal transformations have been studied for a specific case: the PTMTC·EtOH adduct. The crystal structure reveals that included guest solvent molecules participate in the formation of new hydrogen bonds with the carboxylic groups of PTMTC radicals, inducing the disruption of several direct hydrogen bonds among these radicals. As expected, the interruption of direct hydrogen bonds between PTMTC radicals induces large transformations in the magnetic properties. From the ferromagnetic behavior of the α-phase, predominant antiferromagnetic interactions are observed for the inclusion adducts. Interestingly, both structural and magnetic changes are reversible after removal of guest solvent molecules.
AB - Solvent inclusion/evacuation caused variations in the structural and magnetic characteristics of the purely organic porous magnet based on the tricarboxylic-substituted PTMTC radical. Whereas no inclusion is observed for nonpolar solvents, the exposure of crystals of the α-phase of PTMTC to vapors of polar organic solvents with hydrogen acceptor and/or donor functionalities, such as, ethanol, benzoic alcohol, n-decanol, THF, and DMSO results in the inclusion of these solvents in the highly polar tubular channels of the α-phase. The resulting inclusion compounds of formula PTMTC. x(guest) show several structural rearrangements, as confirmed by IR and XRPD (X-ray powder diffraction) measurements. The crystal transformations have been studied for a specific case: the PTMTC·EtOH adduct. The crystal structure reveals that included guest solvent molecules participate in the formation of new hydrogen bonds with the carboxylic groups of PTMTC radicals, inducing the disruption of several direct hydrogen bonds among these radicals. As expected, the interruption of direct hydrogen bonds between PTMTC radicals induces large transformations in the magnetic properties. From the ferromagnetic behavior of the α-phase, predominant antiferromagnetic interactions are observed for the inclusion adducts. Interestingly, both structural and magnetic changes are reversible after removal of guest solvent molecules.
KW - Host-guest systems
KW - Hydrogen bonds
KW - Magnetic properties
KW - Radicals
KW - Solvatomagnetism
UR - http://www.scopus.com/inward/record.url?scp=35348939612&partnerID=8YFLogxK
U2 - 10.1002/chem.200700353
DO - 10.1002/chem.200700353
M3 - Article
AN - SCOPUS:35348939612
SN - 0947-6539
VL - 13
SP - 8153
EP - 8163
JO - Chemistry - A European Journal
JF - Chemistry - A European Journal
IS - 29
ER -