Magnetic structure of 1D & 2D electrides by powder neutron diffraction

Materials in which electrons behave as anions are called electrides. Electrides can be likened to stoichiometric F-centre salts in which the electron concentration is high enough to allow them to interact with each other. As a result, these exotic materials exhibit physical properties represented by the metal-insulator transition. We propose to perform temperature-dependent PND experiments on a series of RE2C and RE5Si3 (RE = Y, Gd-Er) carbides and silicides, which have been successfully synthesised by arc-melting. Our aim is to validate the magnetic electride nature of our materials, and to study the presence/absence of defects and impurities such as adventitious O or H.

电子以阴离子形式存在的材料被称为电子盐（electrides）。电子盐可被类比为电子浓度足够高、足以发生相互作用的化学计量比F心盐（F-centre salts）。此类奇异材料会表现出以金属-绝缘体转变为代表的物理特性。我们提议对一系列通过电弧熔炼成功合成的RE₂C与RE₅Si₃型碳化物及硅化物开展温度依赖的极化中子衍射（PND）实验，其中RE代表钇（Y）、钆（Gd）至铒（Er）的稀土元素。本研究的目标是验证所制备材料的磁性电子盐特性，并探究材料中是否存在氧（O）、氢（H）等外来缺陷与杂质。