Photochemical formation of ferrimagnetic chains from a pair of polymeric complexes made of octahedral bis(hexafluoroacetylacetonato)manganese(II) with diazodi(4-pyridyl)methane in the cis and trans configurations as repeating units

Satoru Karasawa, Yoko Sano, Takeyuki Akita, Noboru Koga, Tetsuji Itoh, Hiizu Iwamura, Pierre Rabu, Marc Drillon

Research output: Contribution to journalArticle

67 Citations (Scopus)

Abstract

Two kinds of 1:1 manganese complexes a and b of bis(hexafluoroacetylacetonato)manganese(II) coordinated with diazodi(4- pyridyl)methane (1) were prepared. Complexes a and b crystallize in the orthorhombic space group Pbca and in monoclinic C2/c, respectively. Two pyridyl nitrogen atoms from two different molecules of 1 are coordinated in the cis and trans configurations to the manganese ion to form helical and zigzag infinite chains of octahedral manganese complexes in complexes a and b, respectively. The magnetic susceptibilities (χmol) of both crystals before and after irradiation were measured on a SQUID susceptometer and revealed χ(mol)T vs T plots characteristic of ferrimagnetic chains after irradiation for 97 h; interaction between the manganese(II) ion and the photogenerated carbene is antiferromagnetic in both complexes. The antiferromagnetic exchange coupling parameters (J) in the photolyzate of complex a and b were estimated by a theoretical treatment through a procedure of extrapolation by using small rings to be J/k(B) = -34.8 ± 0.8 and -24.4 ± 0.5 K, respectively. Maximum χ(mol)T values of 210 at 5 K for cis- and 246 emu·K·mol-1 at 1.9 K for trans complexes correspond to correlation lengths of 186 and 218 manganese-carbene S = 3/2 units, respectively.

Original languageEnglish
Pages (from-to)10080-10087
Number of pages8
JournalJournal of the American Chemical Society
Volume120
Issue number39
DOIs
Publication statusPublished - Oct 7 1998

    Fingerprint

All Science Journal Classification (ASJC) codes

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

Cite this