Intramolecular through-space antiferromagnetic interactions of cross-conjugated aromatic polyaminium radical gels

Tsuyoshi Michinobu, Manabu Tanaka, Jun Inui, Hiroyuki Nishide

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Highly networked, cross-conjugated aromatic polyamine gels were prepared by palladium-catalyzed polycondensation. The gels were characterized by the cross-polarization magic angle spinning (CP-MAS) 13C NMR and lR spectroscopies, thermogravimetric analysis, and X-ray diffraction. The data confirm that the polymerization proceeded without any side reactions and that the gels possessing the significant thermal stability are composed of the mixtures of polycrystalline and amorphous moieties. Chemical oxidation of the gels with NOPF6 solubilized with 18-crown-6 in CH 2Cl 2 gave the corresponding aminium polyradicals. Appearance of the ESR signals at g = 2.003 and the new IR peaks supported the aminium radical generation. The p-methoxy-substituted aromatic polyaminium radical, the polyradical of poly(2), realized the higher spin concentration of 65% and the enhanced chemical stability than the polyradical of poly(1) without any protecting groups. However, the magnetic measurements of the polyradical of poly(2) did not show any intramolecular ferromagnetic interactions, but indicated very strong intramolecular through-space antiferromagnetic interactions.

Original languageEnglish
Pages (from-to)514-521
Number of pages8
JournalJournal of Nanoscience and Nanotechnology
Volume9
Issue number1
DOIs
Publication statusPublished - 2009 Jan

Fingerprint

Gels
gels
interactions
Magic angle spinning
cross polarization
Chemical stability
Magnetic variables measurement
Polyamines
Palladium
Polycondensation
X-Ray Diffraction
Polymerization
metal spinning
magnetic measurement
Paramagnetic resonance
Thermogravimetric analysis
palladium
Thermodynamic stability
thermal stability
Magnetic Resonance Spectroscopy

Keywords

  • Gel
  • Magnetism
  • Non-kekulé molecule
  • Palladium-catalyzed amination
  • Polyamine

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Chemistry(all)
  • Materials Science(all)
  • Bioengineering
  • Biomedical Engineering

Cite this

Intramolecular through-space antiferromagnetic interactions of cross-conjugated aromatic polyaminium radical gels. / Michinobu, Tsuyoshi; Tanaka, Manabu; Inui, Jun; Nishide, Hiroyuki.

In: Journal of Nanoscience and Nanotechnology, Vol. 9, No. 1, 01.2009, p. 514-521.

Research output: Contribution to journalArticle

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