摘要本次采用密度泛函理论(DFT)中的B3LYP方法和6-3 1G(d)基组计算优化Hn@C30得到稳定构型,然后选择能量最低的构型作为基态构型,并计算它们的物理化学性质。分别为C30-1;C30H4-3(out);C30H8-2(out);C30H6-4(out);C30H12-1(in)。主要研究内容概括如下:86715
(1)通过优化Hn@C30的几何构型,得到Hn@C30的基态构型,确定它的对称性。与C30相比,氢原子的介入使得碳笼发生了轻微膨胀。
(2)通过分析结构稳定性,可知Hn@C30比C30的化学稳定性和热力学稳定性弱,化学活性增强。
(3)通过自然键轨道(NBO)的分析表明了:C原子的NBO电荷主要集中分布在2p轨道,且在C原子内部和C原子之间均有杂化现象。
(4)通过对Hn@C30的振动光谱分析,普遍在频率为3500cm-1左右出现峰值。红外光谱图中有多个较强的振动峰。最强峰值表明该原子是连接碳笼的其他原子做伸缩运动。
(5)磁性分析:C30H6的磁矩为4,其他基态结构为0。
(6)极化率分析:Hn@C30的稳定性比C30弱些 ,离域效应较大一些。
(7)NICS分析:通过对Hn@C30的NICS分析发现,Hn@C30普遍具有芳香性,其中C30H6具有多重芳香性。
毕业论文 关键词: H2@C30;物理化学性质;密度泛函理论
Abstract The geometric structures of Hn@C30 clusters are all optimized systematically by the method of B3LYP on 6-31g basis set, and the stable structures are obtained。 And the physical and chemical properties of the ground state structures are investigated。 They are C30-1;C30H4-3(out);C30H8-2(out);C30H6-4(out);C30H12-1(in)。The research contents and results are as follows:
(1) The geometric structures of Hn@C30 clusters are optimized and we obtains the stable structures of Hn@C30 and its symmetry。 Compared with C30 molecules,it occurres that carbon cage with hydrogen atom involved in slight swells。
(2) By analyzing the structural stability, chemical stability seen Hn@C30 than C30 and thermodynamic stability of weak chemical activity increased。
(3) By analyzing the natural bond orbital (NBO) indicates:NBO charge C atoms mainly concentrated in orbit 2p, s, p orbital hybridization occurs not only in the C atom inside, while in C there is also the phenomenon of hybrid between atoms。
(4) By Hn@C30’s vibrational spectroscopy, the peak shows generally at a frequency of about 3500cm-1。 Infrared spectra have many strong vibration peaks。 The strongest peak indicates that the carbon atom is connected to other atoms cage doing stretching exercise。
(5) Magnetic Analysis: C30H6’s magnetic moment is 4, other state structures are zero。
(6) The polarization ratio analysis: the stability of the electronic structure of Hn@C30 trimer is weaker than C30, Hn@C30 trimer have large number of delocalization。
(7) NICS analysis: by the NICS analysis of Hn@C30, Hn@C30 are generally aromatic,of which C30H6 is multiple aromatic。
Keywords: Hn@C30; physical and chemical properties; density functional theory
目录
第一章 绪论 1
1。1 团簇物理简介 1
1。1。1 团簇的基本概念 1
1。1。2 团簇研究的主要内容 1
1。1。3 团簇研究的意义 2
1。2 小富勒烯的研究进展 2
1。3 本论文研究内容和意义 3
1。3。1 本论文的研究内容 3
1。3。2 本论文的研究意义 Hn@C30的结构和性能研究:http://www.youerw.com/wuli/lunwen_113388.html