权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Theory of Electronic and Nuclear Wavepacket Dynamic (Application to the structure deformation and electron transfer of molucular in laser field)

电子核波包动力学理论（在激光领域分子结构变形和电子转移中的应用）

基本信息

批准号：
12640484
负责人：
KONO Hirohiko
金额：
$ 2.18万
依托单位：
Tohoku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

项目摘要

To understand the ultrafast electronic dynamics in intense fields, we have been developing an efficient grid point method, the dual transformation method, for solving the time-dependent Schrodinger equation for the electronic degrees of freedom of a molecule. We have applied this method to small molecular systems such as H_2. The vibrational degree of freedom is also incorporated in the calculation of H^+_2 without resorting to the Born-Oppenheimer approximation.In a long wavelength case, for H_2, the localized ionic (bond) states H^+H^- and H^-H^+ appear alternately according to the optical cycle, through which tunnel ionization proceeds. After one-electron ionization from H_2, H^+_2 is prepared around the equilibrium internuclear distance of H_2. The bond distance of H^+_2 is then stretched by the applied field. With the help of ab initio molecular orbital calculations, we also demonstrate molecular structure deformations characteristic of intense-field dynamics such as symmetric two-bond stretching of CO_2 cations. The wave packet approach enables visualization of electron-nucleus correlation and two-electron dynamics in intense laser fields.Electronic motion can be controlled by adjusting the intensity, frequency, and pulse length. As an example, we have examined the electronic dynamics of H_2 in a short wavelength case (〜100 nm). Contrary to the long wavelength case, the electron pair is created near the proton at which the dipole interaction energy becomes higher. The nonstationary states H^+H^- and H^-H^+ appear alternately with a period inherent to the molecule even after the incident pulse has fully decayed. Ultrafast electron hopping between the nuclei can be controlled by a second pulse. Using this two-pulse scheme, we are able to enhance or suppress the ionization.

为了理解强场中的超快电子动力学，我们发展了一种有效的网格点方法--对偶变换法，用于求解含时薛定谔方程，计算分子的电子自由度。我们将这种方法应用于H_2等小分子体系。在长波长情况下，H_2的定域离子（键）态H ^+ H ^-和H ^-H ^+按照光学周期交替出现，隧道电离通过这两个态进行。H_2单电子电离后，在H_2的平衡核间距附近生成H ^+_2。H ^+_2的键距被外加电场拉伸。借助从头算分子轨道计算，我们还证明了强场动力学的分子结构变形特征，如CO_2阳离子的对称双键伸缩。波包方法可以直观地观察强激光场中的电子-核关联和双电子动力学，电子的运动可以通过调节强度、频率和脉冲长度来控制。作为例子，我们研究了H_2分子在短波长（~100nm）下的电子动力学。与长波长的情况相反，电子对是在质子附近产生的，此时偶极相互作用能变得更高。非稳态H ^+ H ^-和H ^-H ^+以分子固有的周期交替出现，即使在入射脉冲完全衰减之后也是如此。原子核之间的超快电子跳跃可以由第二脉冲控制。使用这种双脉冲方案，我们能够增强或抑制电离。