Vibrations and soliton dynamics of positively charged polyacetylene chains
Vibrations and soliton dynamics of positively charged polyacetylene chains
复制标题
带正电的聚乙炔链的振动和孤子动力学
DOI：
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发表时间：
1997
期刊：
影响因子：
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通讯作者：
Y. Öhrn
中科院分区：
文献类型：
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作者：
B. Champagne;E. Deumens;Y. Öhrn
对具有正孤子缺陷的聚乙炔小链进行了从头算分子动力学模拟。动力学由外部电场初始化。将碳原子和氢原子的集体运动与具有孤子位移特征的不同长度的带正电聚乙炔链的某些低频振动模式进行了比较。利用各种方案估算的孤子有效质量约为10个电子质量。计算了不同长度的单电荷聚乙炔链的静态线极化率，并与未掺杂链的静态线极化率进行了比较。在耦合Hartree-Fock或随机相位近似的水平上计算了电子对极化率的贡献，并通过调用双谐振子近似来估计振动贡献。孤子缺陷导致电子项的增强，电子项覆盖10-15个碳碳双键，并使电子项的强度增加。
Ab initio molecular dynamics simulation is performed on a small polyacetylene chain with a positive soliton defect. The dynamics is initialized by an external electric field. The collective motion of the carbon and hydrogen atoms are compared to some low frequency vibrational modes of positively charged polyacetylene chains of varying lengths having the characteristics of the soliton displacement. The soliton effective mass estimated using a variety of schemes is found to be about 10 electron masses. The static linear polarizability of singly charged polyacetylene chains of varying lengths is computed and compared with that of undoped chains. The electronic contributions to the polarizability are computed at the level of the coupled Hartree–Fock or the random phase approximation, and the vibrational contributions are estimated by invoking the double harmonic oscillator approximation. The soliton defect causes some enhancement of the electronic term, which covers 10–15 carbon–carbon double bonds, and it ge...