【作者】 王玉敏；

【导师】 闫冰；

【作者基本信息】 吉林大学 ， 原子与分子物理， 2020， 硕士

【摘要】 在原子分子散射中,只有原子分子可与光子有Compton散射的发生,康普顿轮廓（Compton profile,CP）是在Compton散射基础上所得。CP作为探测电子动量密度的工具,能够真实且灵敏的反映原子分子各个轨道电子分布的情况。利用精确的波函数来计算轮廓数据有助于我们提前了解原子分子内部结构特征。同时,组成波函数有s、p、d、f等基函数的存在使得轨道波函数的变化多样。本文基于几种大气中原子分子的轨道波函数计算研究了相应体系的CP,同时通过分子轨道波函数理论研究了AsBr和AsF分子的光谱性质。第一部分研究的内容简述为两方面:（1）对于原子,我们利用数值积分法,分别计算了H、He、Ne和Ar原子的CP,并与CP的实验值进行对比和分析,探究了因轨道形状不同所带来的误差以及笛卡尔坐标计算轮廓结果的合理与否。（2）多原子的分子CP的研究,先计算了最简单的H₂,然后对多轨道的分子（N₂,O₂,H₂O,CO₂）进行CP的求解,计算内容包括各个轨道的方向CP,总的方向CP以及平均CP。探究了笛卡尔坐标的适用范围并猜想了下一步研究的方向。鉴于第五主族卤化物在制药、颜料、除草剂、防腐剂、农药、爆炸性化合物、半导体、冶金行业、纳米技术、电子和光学等诸多领域有着非常广泛的应用,本文基于分子轨道理论和多参考组态相互作用方法,对AsF和AsBr的光谱性质进行了系统的计算研究,研究内容可简述为两方面:（1）AsF和AsBr分子均基于内收缩多参考组态相互作用（internally contracted multireference configuration interaction,icMRCI）加Davidson修正（+Q）方法,并结合全电子Gauss基组下进行计算。两分子计算分别得到拥有两条解离极限的22个Λ-S电子态（AsF）和拥有三个解离极限的34个Λ-S电子态（AsBr）。同时,在计算所得势能曲线（7）potential energy curves,PECs（8）基础上,得到了上述分子部分束缚电子态的光谱常数、主要电子组态成分,永久偶极矩（PDMs）和自旋-轨道耦合矩阵元(spin-orbit matrix elements,H_so)。（2）在基于对自旋-轨道耦合（spin orbit coupling,SOC）效应的考虑,我们对两分子的部分重要的电子态信息进行了较为详细的计算和分析,其中包括光谱常数、弗兰克康普顿因子（Franck-Condon factor,FCFs）、辐射寿命、永久以及跃迁偶极矩（PDMs,TDMs）等等。AsBr分子所获得的跃迁性质包含:TDMs、FCFs和辐射寿命。卤化砷电子态的光谱以及结构在在理论和实验方面的深入研究意义重大。我们对AsF分子各种交叉、避免交叉以及a¹?,b¹Σ⁺,c’¹Π和A³Π,⁵Σ^-和⁵Π相交的预解离机制进行了分析并通过计算我们发现辐射寿命与活性空间的选择有关。更多还原

【Abstract】 In the scattering of atoms and molecules,only atoms and molecules and photons have Compton scattering,and Compton profile（CP）is obtained on the basis of Compton scattering.As a tool to detect electron momentum density,CP can reflect the distribution of electrons in each orbital of atoms and molecules truly and sensitively.Using accurate wave function to calculate the CP data can help us to understand the internal structure characteristics of atoms and molecules in advance.At the same time,the existence of s,p,d,f and other types of basis functions that constitute the wave function makes the variation of orbital wave function varied.In this paper,CP of the corresponding system is studied based on the calculation of molecular orbital wave function of several atoms and molecules in the atmosphere.Meanwhile,the spectral properties of AsBr and AsF molecules are studied by the theory of molecular orbital wave function.The specific research content of the first part can be simply expressed as the following two aspects:（1）For atoms,we use numerical integral method,calculate the H,He,Ne and Ar atoms Compton profiles,and profiles the existing experimental data,this paper compares and analyzes ruled out on the basis of different shape of error is negligible.And whether it is reasonable to calculate the profile by cartesian coordinates.（2）In the study of CP of polyatomic molecules,the simplest H₂ is firstly calculated,and then the CP of multi-orbital molecules（N₂,O₂,H₂O,CO₂）is solved.The calculation includes the direction CP of each orbital,the total direction CP and the average CP.This paper probes into the applicable range of cartesian coordinates and guesses the future research direction.The Group-VA halides are widely used in many fields such as pharmaceuticals,pigments,herbicides,preservatives,pesticides,explosive compounds,semiconductors,nanotechnology in the metallurgical industry,electronics and optics.In this paper,the spectral properties of AsF and AsBr are systematically calculated based on the molecular orbital theory and the multi-reference configuration interaction method.The research contents can be summarized as the following two aspects:（1）For the AsF and AsBr,we based on using internally contracted multi-reference configuration interaction with the addition of Davidson correction（icMRCI+Q）method,and combined with full electronic computing under gaussian basis set.Two molecular computing has two dissociation limit of 22Λ-S electronic states（AsF）and has three dissociation limit of 34Λ-S electronic state（AsBr）.At the same time,based on the potential energy curves（PECs）,we obtained the spectroscopic constants of the above molecular partially bound electron states,the main electron configuration components,permanent dipole moment（PDMs）and spin-orbit coupling matrix elements(H_so).（2）After considering the spin-orbit coupling（SOC）effect,we calculated and analyzed some important electronic state information of the two molecules in detail,including the spectroscopic constants,Frank-Compton factor（FCFs）,radiative lifetime,permanent and transition dipole moment（PDMs,TDMs）.We obtain the transition properties of AsBr molecules including TDMs FCFs and radiative lifetime.The further study of the spectra and structures of the electronic states of arsenic halide is of great significance in theory and experiment.We analyzed the pre-dissociation mechanisms of AsF molecules with various avoid crossing and intersection of a¹?,b¹Σ⁺,c’¹Π and A³Π,⁵Σ^-and ⁵Π and found that the radiative lifetime was related to the selection of the active space.更多还原