TY  - JOUR
AU  - Zhai, Yuan‐Qi
AU  - Deng, Yi‐Fei
AU  - Fu, Zhendong
AU  - Feng, Erxi
AU  - Su, Yixi
AU  - Shiga, Takuya
AU  - Oshio, Hiroki
AU  - Zheng, Yan‐Zhen
TI  - Reentrant Spin Glass and Large Coercive Field Observed in a Spin Integer Dimerized Honeycomb Lattice
JO  - Advanced functional materials
VL  - 31
IS  - 1
SN  - 1616-3028
CY  - Weinheim
PB  - Wiley-VCH
M1  - FZJ-2020-04092
SP  - 2004744
PY  - 2021
AB  - 2D magnetic materials with dimerized honeycomb lattices can be treated as mixed‐spin square lattices, in which a quantum phase transition may occur to realize the Bose–Einstein condensation of magnons under reachable experimental conditions. However, this has never been successfully realized with integer spin centers. Herein, a spin integer (S = 2) dimerized honeycomb lattice in an iron(II)‐azido compound [Fe(4‐etpy)2(N3)2]n (FEN, 4‐etpy = 4‐ethylpyridine) is realized. Morphology characterization by transmission electron microscopy, scanning electron microscopy, and atomic force microscopy spectroscopies show that the thinnest place of the sample is ≈13 nm, which is equal to ten layers of the compound. In contrast to the common magnetic properties of long‐range magnetic ordering, Mössbauer and polarized neutron scattering studies reveal that FEN exhibits a reentrant spin glass behavior owing to competing ferro‐ and antiferromagnetic exchange‐coupling interactions within the lattice. Two spin glass phases with disparate canting angles are characterized at 39 and 28 K, respectively. By using Curély's model, two exchange‐coupling constants (J1 = +35.8 cm−1 and J2 = −3.7 cm−1) can be simulated. Moreover, a very large coercive field of ≈1.9 Tesla is observed at 2 K, making FEN a “very hard” van der Waals 2D magnetic material.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000572983200001
DO  - DOI:10.1002/adfm.202004744
UR  - https://juser.fz-juelich.de/record/885795
ER  -