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arXiv · 2104.07287

Super strong paramagnetism induced by polar functional groups and water

Abstract

We experimentally demonstrate that some commonly used materials such as cellulose acetate and chitin which are traditionally considered to be non-magnetic show super strong paramagnetism in aqueous solutions under ambient conditions when they are agglomerated by nanoparticles. Theoretical computations show that strongly polar functional groups can reduce the potential barrier for a singlet-triplet interconversion with the help of surrounding water, inducing the magnetic moments. These magnetic moments distributed on the surfaces of the nanoparticles, which make a large number of magnetic moments gather in a very small space, greatly enhance the alignment of the moments along and amplify the effect of the external magnetic field, resulting in the super strong paramagnetism. Our findings suggest that the polar functional group may always induce paramagnetism and the magnetic effect may be universal as the electric effects since the polarization is very common in materials.

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Jihong Wang, Yizhou Yang, Jie Jiang, Liuhua Mu, Guosheng Shi, Yongshun Song, Haijun Yang, Peng Xiu, Haiping Fang. 2021-04-15. Super strong paramagnetism induced by polar functional groups and water. https://arxiv.org/abs/2104.07287

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