Synthesis, crystallography, and magnetic characterization of bis(aminoxyl) 1 and its 2:1 complex with Mn(hfac)2 (2) are described. X-ray structure of 2 (at 20 K) provides one of the rare examples of discrete molecules found for the complexes of Mn(hfac)2 and bis(aminoxyls). The differences in conformations of the bis(aminoxyl) moieties in 1 and 2 lead to ferromagnetic and antiferromagnetic exchange coupling through the 1,3-phenylene moiety, in 1 and 2, respectively, as determined by SQUID susceptometry. DFT calculations (at the crystallographic geometries) give the triplet and the singlet ground states for I and for bis(aminoxyl) in 2, respectively. Two analogous conformations of the bis(aminoxyl) are proposed to be responsible for the unprecedented S-shaped time dependence for the conversion from the singlet to the triplet state of 1 in 2-methyltetrahydrofuran.
- DFT calculations
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry