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Title: Direct observation of the magnetic anisotropy of an Fe(II) spin crossover molecular thin film
Abstract In this work, we provide clear evidence of magnetic anisotropy in the local orbital moment of a molecular thin film based on the SCO complex [Fe(H2B(pz)2)2(bipy)] (pz = pyrazol−1−yl, bipy = 2,2′−bipyridine). Field dependent x-ray magnetic circular dichroism measurements indicate that the magnetic easy axis for the orbital moment is along the surface normal direction. Along with the presence of a critical field, our observation points to the existence of an anisotropic energy barrier in the high-spin state. The estimated nonzero coupling constant of ∼2.47 × 10−5eV molecule−1indicates that the observed magnetocrystalline anisotropy is mostly due to spin–orbit coupling. The spin- and orbital-component anisotropies are determined to be 30.9 and 5.04 meV molecule−1, respectively. Furthermore, the estimatedgfactor in the range of 2.2–2.45 is consistent with the expected values. This work has paved the way for an understanding of the spin-state-switching mechanism in the presence of magnetic perturbations.  more » « less
Award ID(s):
2003057
PAR ID:
10430958
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
Journal of Physics: Materials
Volume:
6
Issue:
3
ISSN:
2515-7639
Page Range / eLocation ID:
Article No. 035010
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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