氧原子掺杂铍团簇结构和性质的理论研究

发布时间：2018-06-28 23:46

本文选题：Be_n团簇 + 掺杂团簇　；参考：《吉林大学》2017年硕士论文

【摘要】：团簇是由几个乃至上千个原子、分子或离子通过物理或化学结合力组成相对稳定的微小粒子,它们所具有的独特的结构,电子特性,磁性和光学性质依赖于它们的元素组成、尺寸和几何形状等。本文基于密度泛函理论研究了氧掺杂的铍团簇,得到了团簇的结构及性质随着氧原子数的演变规律,氧原子的掺杂对纯铍团簇的影响及效应,团簇的幻数等等。我们以大量的初始结构为基础,通过B3PW91水平下使用6-311+G(d)基组进行计算,获得了Be_nO(n=1-12)的12个最低能量结构。应用QCISD(T)的方法得到这些结构的单点能,进而对Be_nO和Be_(n+1)团簇的平均结合能(Eb),二阶能量差分(Δ~2E),解离能(ΔE),垂直电子亲和势(VIP)和垂直电离势(VEA)等各种能量及电子性质进行了对比分析。根据这些性质的相关数据分析显示Be_(11)O具有独特稳定性。最后本论文使用自然键轨道(NBO)和电子局域化函数(ELF)方法分析了Be_(11)O的电子结构。Be_(11)O可以看作由Be_(11)~(2+)和O~(2-)组成的离子化合物。稳定性来自两方面:其中,O~(2-)具有8个价电子,满足8电子规则。而Be_(11)~(2+)具有闭壳层电子构型包含20个价电子,致使它本身呈现独特的稳定性。并与团簇电子壳层模型(CSM)中的结论相符。通过本论文的工作不但发现了一种新型的非金属掺杂的金属团簇,而且为实验研究者在实验中对此类复合物的合成与研究提供了理论根据和参考。
[Abstract]:Clusters are relatively stable tiny particles composed of several or even thousands of atoms, molecules or ions through physical or chemical binding forces. Their unique structure, electronic properties, magnetic and optical properties depend on their elemental composition. Size and geometry, etc. Based on density functional theory (DFT), the structure and properties of oxygen doped beryllium clusters are studied. The evolution of the structure and properties with the number of oxygen atoms, the influence and effect of oxygen doping on pure beryllium clusters, the magic number of clusters and so on are obtained. Based on a large number of initial structures, using 6-311G (d) basis set at B3PW91 level, we have obtained 12 lowest energy structures of Ben O (nn ~ (1-12). The single point energy of these structures is obtained by QCISD (T) method, and the energy and electronic properties of BeN O and Ben 1 clusters are compared and analyzed, such as the average binding energy (EB), the second order energy difference (螖 E), the dissociation energy (螖 E), the vertical electron affinity potential (VIP) and the vertical ionization potential (VEA). According to the data analysis of these properties, Be11O has unique stability. Finally, the natural bond orbital (NBO) and electron localization function (ELF) methods are used to analyze the electronic structure of Be11O. Be11O can be regarded as an ionic compound composed of Be11 ~ (2) and O ~ (2-). The stability comes from two aspects: the O ~ (2-) has eight valence electrons and satisfies the 8-electron rule. Be11 ~ (2) has a closed shell electron configuration containing 20 valence electrons, which leads to the unique stability of Be11 ~ (2). The results are consistent with those obtained in the cluster electron shell model (CSM). Through the work of this thesis, not only a new kind of nonmetal doped metal cluster is found, but also the theoretical basis and reference for the synthesis and study of this kind of complex in the experiment are provided.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O641.1

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