Lu Fang, Li Jia-Xin, Guo Wen-Xiao, Wang Bao-Lin, Zhang Yi-Quan
Jiangsu Key Lab for NSLSCS, School of Physical Science and Technology, Nanjing Normal University, Nanjing 210023, P. R. China.
Inorg Chem. 2021 Jan 18;60(2):1007-1015. doi: 10.1021/acs.inorgchem.0c03115. Epub 2021 Jan 7.
Density functional theory (DFT) and calculations were performed to probe the origin of the magnetic relaxation barriers for two finite single-chain magnets (SCMs) featuring a one-dimension chain, Co(hfac)(R-NapNIT) (R-NapNIT = 2-(2'-(-)naphthyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, R = MeO () or EtO ()). Our calculations show that the strong intrachain Co-Co exchange coupling interactions transmitted by radicals can contribute much more than ionic anisotropy to the height of the reversal barrier of magnetization for the single-chain magnets (SCMs) with |2| < |4/3|. In addition, the anisotropic energy barrier Δ decreases with the decrease of |2/| ratio and finally vanishes in the limit of broad domain walls (|2| < < |4 /3|). Therefore, the total magnetic relaxation energy barriers of two SCMs mostly originate from the correlation energy barrier Δ deriving from the indirect ferromagnetic interaction between Co-Co transmitted by the strong Co-radical antiferromagnetic interactions.
进行了密度泛函理论（DFT）计算，以探究两种具有一维链结构的有限单链磁体（SCMs），即Co(hfac)(R - NapNIT)（R - NapNIT = 2-(2'-(-)萘基)-4,4,5,5 - 四甲基咪唑啉 - 1 - 氧基 - 3 - 氧化物，R = MeO () 或EtO ()）的磁弛豫势垒的起源。我们的计算表明，对于|2| < |4/3|的单链磁体（SCMs），由自由基传递的强链内Co - Co交换耦合相互作用对磁化反转势垒高度的贡献比离子各向异性大得多。此外，各向异性能垒Δ随着|2/|比值的减小而降低，最终在宽畴壁极限（|2| < < |4 /3|）中消失。因此，两种SCMs的总磁弛豫能垒主要源于由强Co - 自由基反铁磁相互作用传递的Co - Co间接铁磁相互作用产生的关联能垒Δ。
