Demonstration of the thermally induced high spin–low spin transition for a transparent spin crossover complex film [Fe(II)(H-trz) 3]-Nafion (trz = triazole)

• Published in: Polyhedron Vol. 24; no. 16; pp. 2909 - 2912
• Main Authors: Nakamoto, Akio, Kojima, Norimichi, XiaoJun, Liu, Moritomo, Yutaka, Nakamura, Arao
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 17.11.2005
• Subjects: EXAFS; Ion-exchange film; LIESST; Nafion; Spin-crossover complex film; Spin-crossover complex film; LIESST; Ion-exchange film; Nafion; EXAFS
• ISSN: 0277-5387
• DOI: 10.1016/j.poly.2005.03.040

The spin transition in [Fe II(H-trz) 3] -Nafion takes place around room temperature. The color changes from transparent to purple with decreasing temperature. Transparent spin crossover complex films [Fe(R-trz) 3]-Nafion (R = H, NH 2), have been prepared by using an ion-exchange resin (Nafion) as counter anion. We observed the spin crossover phenomenon around room temperature and revealed the LIESST (light-induced excited spin state trapping) effect at 4.2 K, for these films. In ICMM2004, we have demonstrated the spin crossover behavior as thermochromism for the transparent [Fe(H-trz) 3]-Nafion film, where the spin transition takes place between the high spin (HS) state (colorless at 300 K) and the low spin (LS) state (purple color at 77 K). Here, we review the synthesis and the spin crossover phenomenon for the spin crossover complex film [Fe(H-trz) 3]-Nafion.