运用含时密度泛函理论和分子动力学相结合的方法,研究了C5分子线在强激光场中的电离激发.研究发现,当考虑激光强度对C5分子线激发的影响时,激光强度越强,分子吸收的能量越多,电离也越早,最终电离的电子也越多,而且沿激光极化方向的偶极矩的变化及峰值也越大.关于激光极化方向对C5分子线激发的影响的研究表明,当激光极化方向沿着C5分子线轴向时,分子的电离大大增强,x方向的激光脉冲仅能激发起x方向的偶极振荡,而y方向的激光脉冲仅能激发起y方向的偶极振荡,而且x方向的激光脉冲激发的偶极振荡强.研究还表明,当激光极化方向沿着C5分子线轴向时,尽管由于电离增强而导致C5分子线C—C键振动的同步性变差,但在两种激光极化方向情况下,C5分子线的振动模式与中性C5分子线的振动模式相同.
Combining the time-dependent density functional theory with molecular dynamics of ions the excitation of the carbon wire C5 is explored. It is found that the stronger the laser intensity, the more energies are absorbed by C5 and the earlier the ionization takes place and the more electrons are emitted when considering the effect of the laser intensity on the excitation of the carbon wire C5. The study of the influence of the polarization of the laser pulse on the excitation of C5 indicates that the ionization is enhanced and the dipole moment along the laser polarization is strengthened when the laser polarization is along the molecular axis, and the x-direction polarized laser pulse can only excite the dipole oscillation along the x axis, and the y-direction polarized one can only excite Dy. Furthermore, it is found that the synchronicity of the vibration of carbon bonds changes a little due to the enhanced ionization when the laser polarization is along the molecular axis, while the vibration modes of ionized carbon wire C5 are the same as those of the neutral carbon wire C5.