A research team led by Associate Prof. LI Xingxing and Prof. YANG Jinlong from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS)has developed a groundbreaking chemical method for two-dimensional metal-organic lattices.
Their results were published in Nano Letters on Oct. 2nd.
In spintronics, it is paramount to develop an efficient way to reversibly control the spin order of materials. Though various physical methods have been proposed, chemically achieving this has posed significant challenges.
Researchers proposed the utilization of the well-recognized lactim−lactam tautomerization process to reversibly modulate the magnetic phase transition in two-dimensional (2D) organometallic lattices. This revelation offers novel pathways for controlling the electrical and magnetic characteristics of materials.
The spin state of an organic linkers undergoes a transformation from a singlet state to a doublet state due to the lactim−lactam tautomerization.
Schematic illustration of the magnetic phase change in a 2D metal-organic lattice induced by the lactic-lactam tautomerization reaction (Image by USTC)
Using chemical means to control the spin state of materials has several potential advantages over physical methods. It can be done at room temperature, which makes it more practical for real-world applications. Additionally, chemical reactions can be precisely controlled, enabling more precise control over the spin state of materials.
In their study, the team used the compound called 2D organometallic lattices, which has a unique structure that allows its magnetic phase to be changed using the lactim-lactam tautomerization. Researchers demonstrated that this reaction could be used to reversibly switch the magnetic state of the material from antiferromagnetic to ferrimagnetic.
(a-c) Geometric structure, ground state spin density distribution, and band structure of the lactam-type Cr-pyrazine metal-organic lattice. (d-f) Geometric structure, ground state spin density distribution, and band structure of the lactim-type Cr-pyrazine metal-organic lattice (Image by USTC)
The team’s findings pave the way for further research in this area. By exploring other chemical reactions that can influence the spin state of materials, it may be possible to develop even more advanced spintronic devices in the future.
paper link: https://pubs.acs.org/doi/10.1021/acs.nanolett.3c03060
(Written by LI Rui, edited by HUANG Rui, USTC News Center)