Spin-crossover dendrimers: Generation number-dependent cooperativity for thermal spin transition

Tsuyohiko Fujigaya, Dong Lin Jiang, Takuzo Aida

Research output: Contribution to journalArticle

52 Citations (Scopus)

Abstract

Poly(benzyl ether) dendrons having a focal triazole unit (Gntrz: trz = triazole; n = generation number = 0-2) were found to react with (MeSO 3)2Fe to form dendritic coordination polymers ([Fe(Gntrz)3]-(MeSO3)2·2H2O) that undergo the thermal spin transition. When the generation number of the dendritic unit was larger (n = 0 → 1 → 2), the average degree of polymerization (Dp = 20 → 10 → 3) and spin-crossover temperature (Tc = 335 → 315 → 300 K) of the resulting polymer were lower. However, the abruptness of the spin transition was not monotonically dependent on the generation number; (G1trz)Fe exhibited an abrupt spin transition with a temperature width of only 10 K, while the smallest and largest members of the (Gntrz)Fe family both displayed a rather broad spin-transition temperature width (30 (n = 0) and 50 K (n = 2)). X-ray diffraction and calorimetric analyses indicated the presence of a discotic columnar core-shell assembly with a crystal lattice best occupied by a C 3v symmetric array of medium-sized (G1trz)-Fe.

Original languageEnglish
Pages (from-to)5484-5489
Number of pages6
JournalJournal of the American Chemical Society
Volume127
Issue number15
DOIs
Publication statusPublished - Apr 20 2005
Externally publishedYes

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Dendrimers
Triazoles
Polymers
Hot Temperature
Shells (structures)
Temperature
Transition Temperature
X-Ray Diffraction
Crystal lattices
Polymerization
Ether
Superconducting transition temperature
Ethers
X ray diffraction

All Science Journal Classification (ASJC) codes

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry

Cite this

Spin-crossover dendrimers : Generation number-dependent cooperativity for thermal spin transition. / Fujigaya, Tsuyohiko; Jiang, Dong Lin; Aida, Takuzo.

In: Journal of the American Chemical Society, Vol. 127, No. 15, 20.04.2005, p. 5484-5489.

Research output: Contribution to journalArticle

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