EAPSI:Investigating the Electronic and Magnetic Properties of Composites with Trapped Electrons

离子化合物是一种化合物，其中正离子和负离子通过离子键结合在一起。带正电荷的离子叫阳离子，带负电荷的离子叫阴离子。电子是一类独特的以不可还原的阳离子和电子为阴离子的离子化合物。这些阴离子电子既不与特定的原子或键相关，也不完全离域，但它们定域在晶体空穴中。由于这些电子不受任何离子的束缚，电子在低电场下对于像冷阴极荧光灯这样的高效率发光设备具有很大的冷发射潜力。这些电子材料大多对空气和温度敏感，但最近发展起来的几种新的层状二维电子材料使电子材料的实际应用成为可能。二维电子体还因为其独特的电学性质，如超导电性，以及由于其低的电子功函数而在有机发光二极管(OLED)中的潜在应用而吸引了科学家。电子材料的理论研究对于开发新的电子材料，以选择具有增强电子性质的候选化合物是必不可少的。这项研究将与韩国水原市成均馆大学(SKKU)综合纳米结构物理中心(CINAP)著名材料科学专家Sung wng Kim博士一起进行。理论模拟将使用基于密度泛函理论(DFT)的第一性原理计算，如维也纳从头算模拟程序(VASP)所实现的那样。在层状结构的二维电体中，选择了两种碳化物(Y2C和Dy2C)和两种氮化物(Sr2N和Ba2N)。建议进行理论计算，并与东道主研究顾问小组的实验结果进行比较。该计划将利用第一性原理计算获得Y2C、Dy2C、Sr2N和Ba2N的结构、电子、磁性和表面性质，以阐明电子材料的结构和材料性能之间的关系。该奖项是与韩国国家研究基金会合作资助的。

An ionic compound is a chemical compound in which positive and negative ions are held together by ionic bonds. The positively charged ions are called cations and the negatively charged ions are called anions. Electride is a unique class of ionic compound with nonreducible countercations and electrons as anions. These anionic electrons are neither associated with specific atom or bond nor fully delocalized, but they are localized within the crystal voids. Since these electrons are not bound to any ions, electrides have a great potential for cold emission in a low electric field for high-efficiency light-emitting devices like cold-cathode fluorescent lamps. Most of these electrides are sensitive to air and temperature, but recently several new layer structured two-dimensional electrides have been developed making the practical application of electrides possible. Two-dimensional electrides also attract scientists because of their unique electronic properties such as superconductivity and for the potential application for organic light-emitting diode (OLED) due to their low electron work function. Theoretical study of electrides is essential for developing new electrides for selecting candidate compounds with enhanced electronic properties. This research will be conducted with Dr. Sung Wng Kim, a noted expert in material science, at Center for Integrated Nanostructure Physics (CINAP), Sungkyunkwan University (SKKU), Suwon, Republic of Korea. Theoretical simulations will use the first-principles calculations based on the Density Functional Theory (DFT) as implemented in the Vienna Ab initio Simulation Package (VASP). Among layer-structure two-dimensional electrides, two carbides (Yttrium carbide - Y2C and Dysprosium carbide - Dy2C) and two nitrides (Strontium nitride - Sr2N and Barium nitride - Ba2N) have been selected for the proposed project. It is proposed to do theoretical calculations and compare with the experimental results obtained in the host research advisor's group. The proposed project will obtain structural, electronic, magnetic and surface properties of Y2C, Dy2C, Sr2N and Ba2N using first principles calculations to elucidate the relationship between structure and material properties of electrides. This award is funded in collaboration with the National Research Foundation of Korea.