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In the present work,we adopt the ccsd/6-31g(d) method to optimize the ground state structure and calculate the vibrational frequency of the Si2N molecule.The calculated frequencies accord satisfactorily with the experimental values,which helps confirm the ground state structure of the molecule.In order to find how the external electric field affects the Si2N molecule,we use the density functional method B3P86/6-31g(d) to optimize the ground state structure and the time-dependent density functional theory TDDFT/6-31g(d) to study the absorption spectra,the excitation energies,the oscillator strengths,and the dipole moments of the Si2N molecule under different external electric fields.It is found that the absorption spectra,the excitation energies,the oscillator strengths,and the dipole moments of the Si2N molecule are affected by the external electric field.One of the valuable results is that the absorption spectra of the yellow and the blue-violet light of the Si2N molecule each have a red shift under the electric field.The luminescence mechanism in the visible light region of the Si2N molecule is also investigated and compared with the experimental data. 相似文献
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用两态原子轨道展开方法研究计算了中高能α粒子与类氦离子(Be2+,B3+,C4+,N5+,O6+)和Li原子碰撞中电子俘获截面。结果表明,在中高能区的结果与实验较好地符合。 相似文献
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用模型势方法对正电子与氪、氙原子散射角分布进行了系统计算,通过对算得的微分截面(散射角从20°-160°)的数据分析,结合作者以前对正电子与氦、氖、氩原子散射角分布的研究结论,总结出了低能正电子与稀有气体原子散射角分布规律 相似文献
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本文根据文献〔1〕提出的电子瞬时配对形成未饱和共价键的物理模型,利用ACQM〔2〕方法对H_(9)体心立方结构和能量进行了计算和研究。获得了这种构型的势能曲线,结果表明在r=1.55a_(0)处有一极小能量—5.10a.u.。 相似文献
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Numerical exploration of population transfer of Rydberg-atom by single frequency-chirped laser pulse 下载免费PDF全文
This paper has calculated that Rydberg atoms can be transferred to states of lower principal quantum number by exposing them to a frequency chirped microwave pulse. The atoms experience the consequence: 70p-69s-68p-67s-66p by a constant amplitude field in the adopted model. This study shows that the complete population transfer is related to the chirp rate and the carrier frequency. 相似文献
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通过非线性变换和特殊设计结点的B样条函数方法研究计算了囚禁于巴基球内的钠原子的里德堡能级结构和振子强度.计算结果表明,巴基球等效势阱深度可以有选择的影响和改变里德堡原子的特性. 相似文献
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应用第一性原理对CO分子在Co(0001)表面( squar3× squar3)R30°−CO吸附结构进行不同形式的密度泛函计算研究. 结果表明:吸附能修正前,仅RPBE泛函预测CO顶位吸附;而修正后PW91、PBE和PKZB泛函结果也表明CO分子Top顶位吸附最稳定,与实验结果一致.对于吸附几何结构、吸附前后体系功函、C-O伸缩振动频率和CO分子态密度分布,所有泛函给出一致的结果,且与已有实验结果符合. 相似文献
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采用密度泛函B3P86和组态相互作用方法在6-311G**基组水平上计算了二氧化硅分子从基态到前5个激发态的跃迁波长、振子强度、自发辐射系数An0和吸收系数B0n(n=1—5).研究了外电场对二氧化硅分子激发态的影响规律. 结果表明,随外电场强度增大,最高占据轨道与最低空轨道能隙变小,占据轨道的电子易于激发至空轨道. 因而在外场作用下分子易于激发.
关键词:
2')" href="#">SiO2
激发态
外电场 相似文献
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Field-free molecular orientation induced by combined femtosecond single- and dual-color laser pulses:The role of delay time and quantum interference 下载免费PDF全文
The coherent control of field-free molecular orientation of CO with combined femtosecond single- and dual-color laser pulses has been theoretically studied. The effect of the delay time between the femtosecond single- and dual-color laser pulses is discussed, and the physical mechanism of the enhancement of molecular orientation with pre-alignment of the molecule is investigated. It is found that the basic mechanism is based on the creation of a rotational wave packet by the femtosecond single-color laser pulse. Furthermore, we investigate the interference between multiple rotational excitation pathways following pre-alignment with femtosecond single-color laser pulse. It is shown that such interference can lead to an enhancement of the orientation of CO molecule by a factor of 1.6. 相似文献