Photo-switchable spin-crossover iron(III) compound based on intermolecular interactions

  • Tetsuya Shimizu
  • Yasuka Komatsu
  • Hidenobu Kamihata
  • Young Hoon Lee
  • Akira Fuyuhiro
  • Seiichiro Iijima
  • Shinya HayamiEmail author
Original Article


Iron(III) spin-crossover compounds, [Fe(qnal)2]CF3SO3·MeOH (1·MeOH) and [Fe(qnal)2]CF3SO3·acetone (1·acetone) were prepared and their spin transition properties were characterized by magnetic susceptibility measurement, Mössbauer spectroscopy and single crystal analysis. Two iron(III) compounds exhibited abrupt spin transition with thermal hysteresis loop (T 1/2↑ = 115 K and T 1/2↓ = 104 K for 1·MeOH, and T 1/2↑ = 133 K and T 1/2↓ = 130 K for 1·acetone). Single crystal analysis revealed both of the structures in high-spin (HS) and low-spin (LS) states for 1·acetone. The difference of bond length between the HS and LS states for 1·acetone was ~0.10 Å, which was corresponding to that of typical iron(III) SCO compounds. Specially, it showed strong intermolecular interactions by ππ stacking formed between the neighbor complexes leading to 2-D sheet. Both 1·MeOH and 1·acetone exhibited LIESST effect when it was illuminated at 1000 nm. We also confirmed that the introduction of strong intermolecular interactions, such as ππ stacking, can play an important role in LIESST effect.


Iron(III) Spin-crossover LIESST Intermolecular interaction 



We thank for the financial support the Grant-in-Aids for Science Research (No. 20350028) from the Ministry of Education, Culture, Sports, Science and Technology of the Japanese Government and for Priority Area “Coordination Programming” (area 2107) from the MEXT of Japan.Y. H. L. was also supported by the JSPS program of Postdoctoral Fellowships for Foreign Researchers (No. 2200341).

Supplementary material

10847_2011_9960_MOESM1_ESM.doc (13 kb)
Crystallographic data (CIF) for 1·MeOH, the selected bond lengths and angles for 1·acetone (Table S1), ORTEP drawings and packing views for 1·acetone at 120 and 200 K (Figs. S1, S2) (DOC 13 kb)
10847_2011_9960_MOESM2_ESM.pdf (655 kb)
Crystallographic data (CIF) for 1·MeOH, the selected bond lengths and angles for 1·acetone (Table S1), ORTEP drawings and packing views for 1·acetone at 120 and 200 K (Figs. S1, S2) (PDF 654 kb)


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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • Tetsuya Shimizu
    • 1
  • Yasuka Komatsu
    • 1
  • Hidenobu Kamihata
    • 1
  • Young Hoon Lee
    • 1
  • Akira Fuyuhiro
    • 2
  • Seiichiro Iijima
    • 3
  • Shinya Hayami
    • 1
    Email author
  1. 1.Department of Chemistry, Graduate School of Science and TechnologyKumamoto UniversityKumamotoJapan
  2. 2.Department of Chemistry, Graduate School of ScienceOsaka UniversityToyonakaJapan
  3. 3.National Institute of Advanced Industrial Science and TechnologyTsukubaJapan

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