引用本文:
【打印本页】   【HTML】   【下载PDF全文】   查看/发表评论  【EndNote】   【RefMan】   【BibTex】
←前一篇|后一篇→ 过刊浏览    高级检索
本文已被:浏览 979次   下载 2020 本文二维码信息
码上扫一扫!
分享到: 微信 更多
小分子硫原子团簇正离子的结构稳定性
陈明旦*,刘明宏,刘建文,焦毓才,张乾二
作者单位E-mail
陈明旦* 固体表面物理化学国家重点实验室,厦门大学化学系,厦门,361005 mdchen@xmu.edu.cn 
刘明宏 固体表面物理化学国家重点实验室,厦门大学化学系,厦门,361005  
刘建文 固体表面物理化学国家重点实验室,厦门大学化学系,厦门,361005  
焦毓才 固体表面物理化学国家重点实验室,厦门大学化学系,厦门,361005  
张乾二 固体表面物理化学国家重点实验室,厦门大学化学系,厦门,361005  
摘要:
用分子图形软件设计出49种硫原子团簇Sn+(n=3~13)的结构,使用B3LYP密度泛函进行几何构型优化和振动频率计算,根据分子的总能量得出最稳定的同分异构体.在硫原子团簇正离子中,大部分原子为二配位成键.带有一、三配位的原子结构的总能量较高.部分最稳定硫原子团簇正离子的构型与最稳定的中性硫原子团簇的构型完全不同.
关键词:  硫原子团簇正离子  Sn+  同分异构体  B3LYP  密度泛函
DOI:10.1088/1674-0068/15/5/357-362
分类号:
基金项目:国家自然科学基金资助项目(29573117)和优秀国家重点实验室研究基金(20023001).
Structural Stabilities of Small Cationic Sulfur Clusters
Chen Mingdan,Liu Minghong,Liu Jianwen,Jiao Yucai,Zhang Qianer
Abstract:
The cations of sulfur clusters exhibit intensities of significance on the mass spectra of sulfur clusters generated in direct laser vaporization. To our knowledge, theoretical investigations on cationic sulfur clusters are rare. Forty-nine isomers of sulfur clusters were acquired by means of the molecular model design, molecular mechanics and semi-empirical PM3 and the recently proposed and widely used B3LYPhybrid, non-local, DFT method with basis set 6-31G*. To look for stable configurations, full geometry optimizations at the 6-31G* level for all sulfur atoms were performed using Gaussian 98 program packages. The initial models were constructed by means of breaking bond(s), making bond(s), adding atom(s), deleting atom(s), rotating fragment(s), translating fragment(s) and merging fragment(s). The one-fold, twofold and three-fold modes for modeling were considered, according to the bonding characteristics of the sulfur atom. Finally a total of eleven structures forS3+, S4+and S5+; ten isomers of S6+and S7+; fifteen isomers of S8+ and S9+ and thirteen isomers of S10+, S11+, S12+and S13+are acquired, respectively. A large number of structural possibilities of non-minimum structures were not covered. According to total energies, the most stable Sn+ (n=3~13) isomers are predicted. The geometry, relative stability and structural rules of these cationic sulfur clusters were described. Some structures of neutral sulfur clusters with true minima transform upon ionization into non-minimum cationic structures and vice versa. The results of a large amount of calculations show that the two-fold coordination is generally favored in sulfur cationic clusters, though some sulfur atoms coordinated with the others in one-fold or three-fold mode are higher in total energy. The most stable isomer of some cationic clusters shows a structure completely different from that of the corresponding neutral cluster. In chain structures, the atoms at the two ends adopt the one-fold mode and the others are in two-fold mode. Theoretical studies on sulfur cationic structures with a three-fold atom are rare. It is unlikely to have a sulfur cationic cluster in cage structure, for the bonding of a three-fold atom are not strong enough. The calculation results can serve as guiding factors for future theoretical studies on large sulfur clusters.
Key words:  Cationic sulfur clusters, Isomers, Sn+, B3LYP, Density functional