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Title: Magnetic anisotropy and relaxation behavior of six-coordinate tris(pivalato)-Co( ii ) and -Ni( ii ) complexes
Experimental and theoretical studies of magnetic anisotropy and relaxation behavior of six-coordinate tris(pivalato)-Co( ii ) and -Ni( ii ) complexes (NBu 4 )[M(piv) 3 ] (piv = pivalate, M = Co, 1 ; M = Ni, 2 ), with a coordination configuration at the intermediate between an octahedron and a trigonal prism, are reported. Direct current magnetic data and high-frequency and -field EPR spectra (HFEPR) of 1 have been modeled by a general Hamiltonian considering the first-order orbital angular momentum, while the spin Hamiltonian was used to interpret the data of 2 . Both 1 and 2 show easy-axis magnetic anisotropies, which are further supported by ab initio calculations. Alternating current (ac) magnetic susceptibilities reveal slow magnetic relaxation at an applied dc field of 0.1 T in 1 , which is characteristic of a field-induced single-ion magnet (SIM), but 2 does not exhibit single-ion magnetic properties at 1.8 K. Detailed analyses of relaxation times show a dominant contribution of a Raman process for spin relaxation in 1 .  more » « less
Award ID(s):
1633870
NSF-PAR ID:
10099992
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Dalton Transactions
Volume:
47
Issue:
30
ISSN:
1477-9226
Page Range / eLocation ID:
10162 to 10171
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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