磁性表面金属卟啉、酞菁分子的磁性及其调控的理论研究

项目名称： 磁性表面金属卟啉、酞菁分子的磁性及其调控的理论研究

项目编号： No.11274284

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 孙霞

作者单位： 中国科学技术大学

项目金额： 75万元

中文摘要： 由有机分子制作的纳米自旋电子器件在信息存储、量子计算等方面具有广泛的应用前景，如何有效地调控有机分子的磁性是分子自旋电子学的关键问题之一。本项目将研究铁磁金属Fe/Co/Ni、反铁磁合金MnFe/MnIr和半金属Fe3O4/CoFe2O4表面上金属卟啉、酞菁分子的结构和磁性，通过化学刺激、物理吸附、外加应力、表面改性和表面缺陷等手段，探讨分子磁性的微观调控及相关物理机制。拟采用密度泛函理论(DFT)方法，结合弱相互作用(van der Waals)的定量计算，获得体系的几何构型、成键特性、电子结构、电荷转移和自旋密度等物理量，分析金属卟啉、酞菁分子与表面的磁相互作用，预测或解释它们在表面的自组装行为以及与体系磁性或电子态的自旋极化相关的实验结果，寻找具有稳定磁性和高电子自旋极化率的体系，探索有效调控分子内磁性的方法和微观机制，为有机分子自旋电子器件的实验研究和应用提供理论依据。

中文关键词： 分子自旋电子器件；酞箐分子；自旋极化；磁性调控；密度泛函计算

英文摘要： The spintronic device by organic molecules has significant applications in information storage and quantum calculation. One of the essential issues is how to tune the magnetism of organic molecules effectively. In this project, the structure and magnetism will be studied for metal porphrin and phythalocyanine molecules on surfaces such as ferromagnetic metal Fe/Co/Ni, antiferromagnetic alloy MnFe/MnIr and half-metal Fe3O4/CoFeO4. The tuning of the magnetism in molecules and the corresponding mechanism will be investigated by several methods such as chemical stimulation, physical adsorption, external strain or stress, surface modification and surface defect. The computational methods are the density functional theory (DFT) combined with the van der Waals calculation. We will calculate the geometric configuration, bonding characteristic, electronic structure, charge transfer and spin density etc., in detail. The magnetic interactions of organic molecules and surfaces will be analyzed. The experimental results will be predicted or explained for the molecule assembling on surfaces and the magnetism or spin polarization of molecular states. The purpose is to seek systems with stable magnetism and high spin polarization, to explore the effective way of tuning magnetism in molecules and the corresponding mechanism. Thi

英文关键词： molecular spintronics；;phthalocyanine molecule；spin polarization；magnetism tunning；density functional calculation