Ferromagnetic interactions between triphenylmethyl radicals through an organometallic coupler

Chemical Communications

Volumn , Issue 7, 1999, Pages 579-580

  Elsner, O ^a   Ruiz Molina, D ^a   Vidal Gancedo, J ^a   Rovira, C ^a   Veciana, J ^a  

^a INSTITUT DE CIÈNCIA DE MATERIALS DE BARCELONA ICMAB CSIC   (Spain)

Author keywords

[No Author keywords available]

Indexed keywords

IRON; ORGANOMETALLIC COMPOUND; POLYCHLORINATED TERPHENYL; RADICAL; TRITYL DERIVATIVE;

ARTICLE; MAGNETISM; SYNTHESIS; TEMPERATURE;

EID: 0033531611     PISSN: 13597345     EISSN: None     Source Type: Journal    
DOI: 10.1039/a900371a     Document Type: Article

References (11)

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7. The spin density on the metallocene units linked to the α-carbon atom of α-nitronyl aminoxyl radicals is very small because the SOMO orbital has a node on this carbon atom and therefore the spin density is transmitted only by a spin polarization mechanism.
8. By contrast, for diradical 1 both unpaired electrons can be delocalized by conjugation onto the ferrocene unit according to the particular topology of the diradical promoting a larger magnetic coupling.
9. O. Armet, J. Veciana, C. Rovira, J. Riera, J. Castañer, E. Molins, J. Rius, C. Miravitlles, S. Olivella and J. Brichfeus, J. Phys. Chem., 1987, 91, 5608.
10. To obtain accurate temperature measurements that ensure the validity of the experimental results, the spectrometer was equipped both with a flowing-helium Oxford ESR-900 cryostat (4.2-100 K), controlled by an Oxford ITC4 temperature control unit, and with a calibrated custom-made double temperature control system for determining accurately the sample temperature. Additional precautions to avoid undesirable satura-tion effects and spectral line broadening were also taken.
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