Premium
Synthesis, X‐Ray Structure, Magnetic Properties, and a Study of Intra/Intermolecular Radical–Radical Interactions of a Triradical TEMPO Compound
Author(s) -
Lloveras Vega,
Badetti Elena,
Wurst Klaus,
VidalGancedo José
Publication year - 2015
Publication title -
chemphyschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.016
H-Index - 140
eISSN - 1439-7641
pISSN - 1439-4235
DOI - 10.1002/cphc.201500462
Subject(s) - intermolecular force , chemistry , radical , radical ion , magnetic susceptibility , x ray , crystallography , photochemistry , computational chemistry , organic chemistry , molecule , physics , ion , optics
A novel triradical compound with a P=S core and three branches functionalized with 2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPO) radicals is synthesized and characterized by IR, 1 H NMR, 31 P NMR, and EPR spectroscopy and MALDI‐TOF mass spectrometry, and its chemical structure is confirmed by X‐ray diffraction analysis. The triradical shows neither spin exchange interactions between its radical units nor detectable dipolar interactions. This is consistent with the separation between the radical units found in its X‐ray diffraction structure, and discounts the existence of intramolecular interactions. This conclusion is confirmed by an EPR concentration study. The concentration at which intermolecular interactions start to appear is determined (5×10 −3 m ) and this concentration should be taken into account as a higher concentration limit when studies on intramolecular radical–radical interactions in polyradicals with similar structure are required. SQUID magnetometry analysis of the compound shows antiferromagnetic interactions between the spin carriers of different molecules; that is, antiferromagnetic intermolecular interactions.