Atomic-Scale Mapping of Spin Redistribution in Chemically Engineered Metal-Organic Complexes
Di'an Wu1, Xiaobin Geng1, Xianglong Wu1
1Spin-X Institute, School of Microelectronics, Center for Electron Microscopy, Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional Materials, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 511442, China.
The Journal of Physical Chemistry Letters
|April 2, 2026
Summary
We engineered molecular spin states by adding an iron atom to iron(II)-phthalocyanine (FePc), creating an FePc(Fe) complex. This modification resulted in asymmetric spin density distribution, controllable via metal atom doping for quantum device applications.
Area of Science:
- Surface science
- Quantum computing
- Molecular magnetism
Background:
- Precise control of molecular spin states is crucial for developing molecule-based quantum devices.
- Atomic-scale manipulation and understanding magnetic interactions are key challenges.
Purpose of the Study:
- To investigate the effect of metal atom doping on the spin state of iron(II)-phthalocyanine (FePc).
- To explore the potential of chemically engineering molecular spin architectures for quantum applications.
Main Methods:
- Fabrication of iron(II)-phthalocyanine complexes with an added iron atom (FePc(Fe)) on a surface.
- Utilizing electron spin resonance spectroscopy implemented in a scanning tunneling microscope (STM-ESR).
- Employing individual titanium atoms as spin sensors to probe spin density distribution.
Main Results:
- Demonstrated significant spin density redistribution within the FePc(Fe) complex.
- Observed a pronounced asymmetric spin distribution, enhanced at the iron-doped lobe and reduced at the central iron atom.
- Confirmed findings through theoretical calculations, validating the doping approach.
Conclusions:
- Metal atom doping is an effective strategy for chemically engineering the spatial symmetry of molecular spin states.
- This approach allows for fine-tuning magnetic interactions in surface-supported molecular spin architectures.
- The study provides insights into designing advanced molecular quantum devices.
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