TY - JOUR
T1 - 4,6-Bis(trifluoromethyl)-N,N′-di-tert-butyl-1,3-phenylenebis(aminoxyl) and its bis(hexafluoroacetylacetonato)manganese(II) complex
T2 - Synthesis, X-ray crystallography, and magnetism
AU - Rajca, Andrzej
AU - Rajca, Suchada
AU - Wongsriratanakul, Jirawat
AU - Ross, Charles R.
N1 - Funding Information:
This research was supported by the National Science Foundation (CHE-9510096 and CHE-9806954). We thank the Nebraska Center for Mass Spectrometry for mass spectral determinations.
PY - 2001/5/30
Y1 - 2001/5/30
N2 - 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.
AB - 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.
KW - 2-Methyltetrahydrofuran
KW - Bis(Aminoxyl)
KW - DFT calculations
KW - Mn(hfac)
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U2 - 10.1016/S0277-5387(01)00671-4
DO - 10.1016/S0277-5387(01)00671-4
M3 - Article
AN - SCOPUS:0035972467
SN - 0277-5387
VL - 20
SP - 1669
EP - 1675
JO - Polyhedron
JF - Polyhedron
IS - 11-14
ER -