...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The journal of physical chemistry, A. Molecules, spectroscopy, kinetics, environment, & general theory >Resonant Multiphoton Fragmentation Spectrum of Niobium Dimer Cation
【24h】

Resonant Multiphoton Fragmentation Spectrum of Niobium Dimer Cation

机译：铌二聚体共振多光子碎裂谱

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Resonant multiphoton fragmentation spectra of niobium dimer cation (Nb_2~+) have been obtained by utilizinglaser vaporization of a Nb metal target. Ions are mass-selected with a time-of-flight mass spectrometer followedby a mass gate and then fragmented with a pulsed dye laser, and the resulting fragment ions are detected witha second time-of-flight reflectron mass spectrometer and multichannel plate. Photon resonances are detectedby monitoring ion current as a function of fragmentation laser wavelength. A rich but complex spectrum ofthe cation is obtained. The bands display a characteristic multiplet structure that may be interpreted as due totransitions from the ground state X~4??_(g)~-to several excited states, (B/D)~4II_(|?u)and~4??_(|?u)~-.The ground stateX~4??_(?à1/2g)~-is derived from the electron configuration |D_u~41|ò_g~221|?_2. The two spin-orbit components are splitby 145 cm~(-1)due to a strong second-order isoconfigurational spin-orbit interaction with the low-lying ~2??_(1/2g)~+state. The vibrational frequencies of the ground sate and the excited-state of Nb_2~+are identified as well asmolecular spin-orbit constants (Aso) in the excited state. The electronic structure of niobium dimer cationwas investigated using density functional theory. For the electronic ground state, the predicted spectroscopicproperties were in good agreement with experiment. Calculations on excited states reveal congested manifoldsof quartet and doublet electronic states in the range 0-30 000 cm~(-1), reflecting the multitude of possibleelectronic promotions among the 4d- and 5s-based molecular orbitals. Comparisons are drawn between Nb_2~+and the prevalent isoelectronic molecules V_2~+/NbV~+/Nb_2/V_2/NbV_2
机译：通过利用Nb金属靶材的激光汽化获得了铌二聚阳离子（Nb_2〜+）的共振多光子碎裂谱。先用飞行时间质谱仪对离子进行质量选择，然后再进行质量门，然后用脉冲染料激光将其碎片化，然后用第二个飞行时间反射电子质谱仪和多通道板检测所得碎片离子。通过监测离子电流作为碎裂激光波长的函数，可以检测到光子共振。获得了丰富但复杂的阳离子光谱。带显示出特征多重结构，可以解释为由于从基态X〜4 ?? _（g）〜-跃迁到几个激发态（B / D）〜4II_（|？u）和〜4？从电子构型| D_u〜41 |ò_g〜221 |？_2导出基态X〜4 ?? _（？à1/ 2g）〜-。这两个自旋轨道的分量被145 cm〜（-1）分开，这是由于在低处的〜2π_（1 / 2g）〜+状态下强烈的二阶同构自旋轨道相互作用。确定了地基的振动频率和Nb_2〜+的激发态以及激发态下的分子自旋轨道常数（Aso）。利用密度泛函理论研究了铌二聚体阳离子的电子结构。对于电子基态，预测的光谱性质与实验吻合良好。对激发态的计算揭示了四重态和双重态电子态的拥塞流形在0-30 000 cm〜（-1）范围内，反映了基于4d和5s的分子轨道中可能存在的大量电子促进作用。在Nb_2〜+和普遍的等电子分子V_2〜+ / NbV〜+ / Nb_2 / V_2 / NbV_2之间进行比较

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号