Non-classical FeII spin-crossover behaviour in polymeric iron(II) compounds of formula [Fe(NH2trz)3]X2xH2O (NH2trz=4-amino-1,2,4-triazole; X=derivatives of naphthalene sulfonate)

(Note: The full text of this document is currently only available in the PDF Version )

Petra J. van Koningsbruggen, Yann Garcia, Epiphane Codjovi, René Lapouyade, Olivier Kahn, Leopold Fournès and Louis Rabardel


Abstract

A new series of iron(ii) spin-crossover materials of formula [Fe(NH2trz)3 ]X2xH2O [X=1-naphthalene sulfonate (1ns), 2-naphthalene sulfonate (2ns), 4-hydroxy-1-naphthalene sulfonate (4OH-1ns), 4-amino-1-naphthalene sulfonate (4NH2-1ns) and 6-hydroxy-2-naphthalene sulfonate (6OH-2ns)] are reported. The structure of these compounds consists of linear chains in which the Fe(ii) ions are linked by triple N1 ,N2-1,2,4-triazole bridges. All compounds show non-classical spin-crossover behaviour. Optical and magnetic measurements recorded upon heating show an abrupt low-spin to high-spin transition accompanied by a pronounced thermochromic effect occuring between 330 and 340 K depending on the anion. Thermogravimetric analyses show that the transition is induced by the removal of the two lattice water molecules, which initially stabilized the low-spin state. The dynamical character of this transition has been monitored by extended 57Fe Mössbauer spectroscopic studies on [Fe(NH2trz)3 ](2ns)2xH2O. Upon cooling, the dehydrated modifications show classical spin-crossover behaviour with hysteresis at much lower temperatures, ranging from 229 to 297 K depending on the anion. [Fe(NH2trz)3 ](2ns)2 represents one of the first iron(ii) spin-crossover materials showing a spin transition in the close vicinity of room temperature (290 K) accompanied by hysteresis (14 K).


References

  1. P. Gütlich, Struct. Bonding (Berlin), 1981, 44, 83 .
  2. J. Zarembowitch and O. Kahn, New J. Chem., 1991, 15, 181 Search PubMed .
  3. P. Gütlich, in Mössbauer Spectroscopy Applied to Inorganic Chemistry, ed. G. J. Long, Modern Inorganic Chemistry Series, Plenum Press, New York, 1984, vol. 1 Search PubMed .
  4. E. König, Prog. Inorg. Chem., 1987, 35, 527 .
  5. P. Gütlich and A. Hauser, Coord. Chem. Rev., 1990, 97, 1 CrossRef .
  6. P. Gütlich, A. Hauser and H. Spiering, Angew. Chem., Int. Ed. Engl., 1994, 33, 2024 CrossRef .
  7. O. Kahn and E. Codjovi, Philos. Trans. R. Soc. London A, 1996, 354, 359 Search PubMed .
  8. O. Kahn, Molecular Magnetism, VCH, New York, 1993 Search PubMed .
  9. O. Kahn, E. Codjovi, Y. Garcia, P. J. van Koningsbruggen, R. Lapouyade and L. Sommier, in Molecule-Based Magnetic Materials, ed. M. M. Turnbull, T. Sugimoto and L. K. Thompson, Symp. Ser. No. 644, ACS, Washington, DC, 1996, p. 298 Search PubMed .
  10. J. G. Haasnoot, in Magnetism: A Supramolecular Function, ed. O. Kahn, Kluwer Academic, Dordrecht, Netherlands, 1996, p. 299 Search PubMed .
  11. O. Kahn, J. Kröber and C. Jay, Adv. Mater., 1992, 4, 718 CrossRef CAS .
  12. C. Jay, F. Grolière, O. Kahn and J. Kröber, Mol. Cryst. Liq. Cryst., 1993, 234, 255 Search PubMed .
  13. J. Kröber, J.-P. Audière, R. Claude, E. Codjovi, O. Kahn, J. G. Haasnoot, F. Grolière, C. Jay, A. Bousseksou, J. Linarès, F. Varret and A. Gonthier-Vassal, Chem. Mater., 1994, 6, 1404 CrossRef .
  14. J. Kröber, E. Codjovi, O. Kahn, F. Grolière and C. Jay, J. Am. Chem. Soc., 1993, 115, 9810 CrossRef CAS .
  15. L. G. Lavrenova, V. N. Ikorskii, V. A. Varnek, I. M. Oglezneva and S. V. Larionov, J. Struct. Chem., 1993, 34, 960 CrossRef .
  16. L. G. Lavrenova, V. N. Ikorskii, V. A. Varnek, I. M. Oglezneva and S. V. Larionov, Koord. Khim., 1986, 12, 207 Search PubMed .
  17. V. A. Varnek and L. G. Lavrenova, J. Struct. Chem., 1994, 35, 842 .
  18. L. G. Lavrenova, V. N. Ikorskii, V. A. Varnek, I. M. Oglezneva and S. V. Larionov, Koord. Khim., 1990, 16, 654 Search PubMed .
  19. L. G. Lavrenova, N. G. Yudina, V. N. Ikorskii, V. A. Varnek, I. M. Oglezneva and S. V. Larionov, Polyhedron, 1995, 14, 1333 CrossRef CAS .
  20. R. Bronisz, K. Drabent, P. Polomka and M. F. Rudolf, ICAME95, Conference Proceedings, 1996, 50, 11 Search PubMed .
  21. E. Codjovi, L. Sommier, O. Kahn and C. Jay, New J. Chem., 1996, 20, 503 Search PubMed .
  22. V. P. Sinditskii, V. I. Sokol, A. E. Fogel'zang, M. D. Dutov, V. V. Serushkin, M. A. Porai-Koshits and B. S. Svetlov, Russ. J. Inorg. Chem., 1987, 32, 1149 .
  23. A. Michalowicz, J. Moscovici, B. Ducourant, D. Cracco and O. Kahn, Chem. Mater., 1995, 7, 1833 CrossRef CAS .
  24. N. V. Bausk, S. B. Érenburg, L. N. Mazalov, L. G. Lavrenova and V. N. Ikorskii, J. Struct. Chem., 1994, 35, 509 .
  25. N. V. Bausk, S. B. Érenburg, L. G. Lavrenova and L. N. Mazalov, J. Struct. Chem., 1995, 36, 925 .
  26. S. B. Érenburg, N. V. Bausk, V. A. Varnek and L. G. Lavrenova, J. Magn. Magn. Mater., 1996, 157/158, 595 CrossRef .
  27. V. A. Varnek and L. G. Lavrenova, J. Struct. Chem., 1995, 36, 104 .
  28. V. Ksenofontov and P. Gütlich, personal communication, 1995 .
  29. Y. Garcia, P. J. van Koningsbruggen, E. Codjovi, R. Lapouyade, O. Kahn and L. Rabardel, J. Mater. Chem., 1997, 7, 857 RSC .
  30. Y. Garcia, P. J. van Koningsbruggen, G. Bravic, P. Guionneau, D. Chasseau, G. L. Cascarano, J. Moscovici, K. Lambert, A. Michalowicz and O. Kahn, Inorg. Chem., submitted Search PubMed .
  31. F. Grandjean, G. J. Long, B. B. Hutchinson, L. Ohlhausen, P. Neill and J. D. Holcomb, Inorg. Chem., 1989, 28, 4406 CrossRef CAS .
  32. K. H. Sugiyarto, D. C. Graig, A. D. Rae and H. A. Goodwin, Aust. J. Chem., 1994, 47, 869 CAS .
  33. K. H. Sugiyarto and H. A. Goodwin, Aust. J. Chem., 1988, 41, 1645 CAS .
  34. M. Sorai, J. Ensling, K. M. Hasselbach and P. Gütlich, Chem. Phys., 1977, 20, 197 CrossRef CAS .
  35. T. Buchen, P. Gütlich, K. H. Sugiyarto and H. A. Goodwin, Chem. Eur. J., 1996, 2, 1134 CrossRef CAS .
  36. Y. Garcia, P. J. van Koningsbruggen, E. Codjovi, R. Lapouyade and O. Kahn, in preparation .
  37. J. Kolnaar and J. G. Haasnoot, personal communication, 1996 .