Aleksandrov Aleksey I, Shevchenko Vitaliy G
Enikolopov Institute of Synthetic Polymeric Material Russian Academy of Sciences, Moscow 117393, Russia.
Materials (Basel). 2023 Feb 2;16(3):1297. doi: 10.3390/ma16031297.
The review examines the effect of radio-frequency superradiance during pulsed mechanochemical activation of polymer composites under high pressure. Mechanochemical activation is implemented in three modes: (a) rheological explosion of polymer composite under rapid uniaxial compression, when an elastic wave pulse occurs in a polymer composite sample and implements the physico-chemical transformations leading to the occurrence of a superradiance pulse; (b) parametric mode, when an elastic wave pulse is introduced from the outside through a waveguide into a composite sample; (c) the mode of rapid pressure release, which also leads to the occurrence of a superradiance pulse. Paramagnetic polymer composites-namely polystyrene-binuclear clusters Co(QH)-O-Co(QH) or Mn(QH)-O-Mn(QH), where QH is a ligand based on QH-3,6-di-tert-butylpyrocatechin)-are considered as objects implementing such processes. These binuclear clusters exhibit the Dzyaloshinskii-Moriya effect, and polymer composites based on them exhibit multiferroic properties. A composite of a molecular magnet in polystyrene matrix (Eu(III)(SQ)·bipy complex with four unpaired electrons on Eu(III) and on SQ ligands; SQ is 3,6-di-tert-butylquinolate paramagnetic ligand) is also considered. The binuclear clusters and europium complexes form 2D nano-objects in the polymer matrix with a diameter of 50-100 nm and a thickness of ~ 1-2 nm. The review considers the formalisms of Dicke, Lorentz, Landau-Lifshitz-Blombergen and Havriliak-Negami equations, which make it possible to conduct a time-frequency analysis of these processes, to obtain data on the relaxation processes of spin and charge density in objects responsible for the process of radio-frequency superradiation. It is also shown that the analysis of electron spin resonance data allows us to provide a probable quantum chemical scheme for the implementation of the radio-frequency superradiance process. The phenomenon of superradiation has a great deal of potential in such areas as energy-saving technologies, wireless power transmission and storage devices. The technique of studying fast mechanochemical processes considered in the review allows us to investigate the mechanisms of interaction of magnetic and electrical subsystems in multiferroics and molecular magnets, which expands the scientific base for the creation of new functional materials and enables the solving of related problems of condensed matter physics.
本综述研究了高压下聚合物复合材料脉冲机械化学活化过程中射频超辐射的效应。机械化学活化以三种模式实现：(a) 聚合物复合材料在快速单轴压缩下的流变爆炸，此时聚合物复合材料样品中会出现弹性波脉冲，并引发物理化学转变，导致超辐射脉冲的产生；(b) 参数模式，即通过波导从外部将弹性波脉冲引入复合材料样品；(c) 快速压力释放模式，这也会导致超辐射脉冲的出现。顺磁性聚合物复合材料——即聚苯乙烯双核簇Co(QH)-O-Co(QH)或Mn(QH)-O-Mn(QH)，其中QH是基于QH-3,6-二叔丁基焦儿茶酚的配体——被视为实现此类过程的对象。这些双核簇表现出Dzyaloshinskii-Moriya效应，基于它们的聚合物复合材料表现出多铁性。还考虑了聚苯乙烯基质中的分子磁体复合材料（Eu(III)(SQ)·bipy配合物，Eu(III)和SQ配体上有四个未成对电子；SQ是3,6-二叔丁基喹啉酸顺磁性配体）。双核簇和铕配合物在聚合物基质中形成直径为50-100 nm、厚度约为1-2 nm的二维纳米物体。本综述考虑了Dicke、Lorentz、Landau-Lifshitz-Blombergen和Havriliak-Negami方程的形式体系，这些方程使得对这些过程进行时频分析成为可能，从而获得负责射频超辐射过程的物体中自旋和电荷密度弛豫过程的数据。还表明，对电子自旋共振数据的分析使我们能够为射频超辐射过程的实现提供一个可能的量子化学方案。超辐射现象在节能技术、无线电力传输和存储设备等领域具有巨大潜力。本综述中考虑的研究快速机械化学过程的技术使我们能够研究多铁性材料和分子磁体中磁子系统和电介质系统的相互作用机制，这扩展了创建新型功能材料的科学基础，并有助于解决凝聚态物理的相关问题。
