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91.
Theoretical Investigation of a Single Molecule Device: Geometrical Configurations and Electronic Properties 下载免费PDF全文
Using the first-principle molecular dynamics simulations, we have studied the molecular geometrical configurations as well as the corresponding electronic structures of a single molecule device assembled by the mechanically controllable break junction technique with variations of the electrode distance. There are some very interesting features varying with the electrode distance. 相似文献
92.
First-principle study of geometries, electronic structures and vibrational spectra of neutral and anionic onion-like [As@Ni12@As20] 下载免费PDF全文
We present results of first-principle study for both neutral and anionic onion-like [As@Ni12@As20]. The ground-states of singly-charged and doubly-charged anions deviate from ideal Ih symmetrical geometry because of Jahn--Teller effect, whereas the triply-charged singlet and neutral quartet have similar stable geometries of Ih symmetry. The infrared and Raman spectra may provide a way to determine various charge states of this molecule with the same symmetry. Based on our systematical calculations, we suggest additional experimental measurements in order to determine the appropriate functional with great confidence, which should be important in the research for future quantum dot devices. 相似文献
93.
Simulation of Ionic Populations in Hot Dense Plasmas via a New Method beyond the Average Atom Model 下载免费PDF全文
In theoretical simulations and analysis of diagnostic measurements for hot dense plasmas in the inertial confinement fusion researches, it is usually necessary to consider thousands of transition arrays between a huge number of ionic energy states. Average atom models are adopted for practical purposes. In order to calculate ionic populations of hot dense plasmas more accurately either in local thermodynamic equilibrium or in non-local thermodynamic equilibrium conditions, a simple method beyond the AA model is proposed. 相似文献
94.
A theoretical time-dependent wave-packet dynamics method is applied to calculate the distribution of vibrational states of hydrogen molecular ions produced in high-energy ionization processes of hydrogen molecules. The isotope effect is elucidated in agreement with the available experimental measurements. Our proposed method should be readily applied in other atomic and molecular processes considering great advances in electronic computation science and technology. 相似文献
95.
The high-energy electronic-impact excitation cross section is directly proportional to the generalized oscillators trength (GOS) of the target atom. The generalized oscillator strengths of helium atom from the ground state to the excited states (2^1S, 2^1P and 3^1D) are calculated using the updated R-matrix codes within the first Born approximation. Our calculation results are in good agreement with the previous theoretical and experimental results at high incident energies. In order to treat the bound-bound and bound-continuum transitions in a unified manner, the GOS density is defined based on the quantum defect theory. We calculate the GOS densities of ^1S, ^1p and ^1D charmels, namely the complete high-energy collision cross sections of electronic-impact excitations into all the n^1S, n^1P and n^1D excited states. In addition to high-energy excitation cross sections, a scheme to calculate the excitation cross sections for entire incident energy range is discussed. 相似文献
96.
在量子数亏损框架下,利用多重散射自洽方法计算了C2 H4 价壳层电离连续区光吸收谱.通过对势形共振的峰位分析,探讨了势形共振对光解离动力学的影响. The photoabsorption spectra in the valence-shell continuum region of C 2H 4 are calculated by the multi-scattering self-consistent-field method in the framework of the quantum defect theory. The energy positions of potential shape resonance are determined. The influence of the potential shape resonance on photodissociation dynamics is discussed. 相似文献
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双电子复合是一种共振辐射复合过程,在这一过程中,一个具有特定能量的自由电子与电离度为q的离子A~(+q)碰撞,形成有两个电子激发的自电离态n_(?)l_(?)nl,该自电离态进一步发射光子,复合成A~(+(q-1))离子,一系列n(?)l_(?)nl自电离态(n_(?)l_(?)l固定,n从有限到无限变化)形成一个通道,本文在相对论单组态理论基础上,具体探讨了类氦铁离子(3s_(1/2)~nP_(1/2))J=(?)通道中,双电子复合速率随n的变化规律,根据本文得到的规律,可以很方便地计算任意离子的任意一
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