密度泛函理论研究Al_(24)N_(24)几何结构、芳香性和光谱性质  

Research on structures,aromaticity and spectral properties of Al_(24)N_(24) through the density functional theory

作　　者：郭雅晶 李秀燕[2] GUO Yajing;LI Xiuyan(Department of Physics,Taiyuan Normal University,Jinzhong,Shanxi 030619,P.R.China;College of Physics,Taiyuan University of Technology,Taiyuan 030024,P.R.China)

机构地区：[1]太原师范学院物理系,山西晋中030619 [2]太原理工大学物理学院,太原030024

出　　处：《重庆大学学报》2024年第11期112-119,共8页Journal of Chongqing University

基　　金：国家自然科学基金资助项目(12004276);山西省高等学校科技创新资助项目(2023L236)。

摘　　要：通过密度泛函理论(density functional theory,DFT)结合B3LYP/6-31g(d)基组对Al_(24)N_(24)团簇的几何电子结构进行全面优化和物理化学性质模拟分析。研究结果表明,Al_(24)N_(24)团簇的4种基态稳定结构点群依次为S_(4)、C_(2)、S_(8)、O;4种Al_(24)N_(24)团簇气相下既非p型输运材料,亦非n型输运材料,也不存在双极性传递性质,但是这些团簇有利于空穴传输;在优化好的Al_(24)N_(24)团簇气相结构下,研究了它们的核独立化学位移值(nuclear independent chemical shift value,NICS),由NICS得出4种同分异构体均具有芳香性;这4种同分异构体的红外和拉曼分子振动谱表明,各分子内部振动模式对红外和拉曼振动峰值的分布具有重要的影响,随着体系内八元环数量的增多,红外谱出现轻微蓝移现象,拉曼谱中未观测到此现象;特别是对称性为O的Al_(24)N_(24)分子,内部含有6个八元环,这也导致它的振动谱不同于其他三者。The physical-chemical properties and electronic structures of Al_(24)N_(24)were optimized using density functional theory(DFT)at the B3LYP/6-31g(d)level.The results revealed four stable ground-state structures with point groups S_(4),C_(2),S_(8),and O for Al_(24)N_(24)clusters.None of the Al_(24)N_(24)clusters exhibited p-type or n-type transport behavior in the gas phase,nor did they display bipolar characteristics;however,all four clusters favored hole transport.Based on the optimized gas-phase structures,nuclear independent chemical shift(NICS)values were calculated,confirming the aromaticity of all isomers.The IR-Raman spectra of the four clusters were analyzed,revealing that the internal vibration modes of each molecule significantly influenced the distribution of IR and Raman peak values.A slight blue shift in the IR spectra was observed with an increasing number of eight-membered rings,while no such shift was detected in the Raman spectra.Notably,the Al_(24)N_(24)molecule with O symmetry contained six eight-membered rings,leading to vibrational spectra distinct from the other three clusters.

关 键 词：芳香性 光谱性质 密度泛函理论 

分 类 号：O561[理学—原子与分子物理]