| Author Name | Affiliation | E-mail | | Min-jun Feng | Beijing National Laboratory for Molecular Sciences, Molecular Reaction Dynamics Laboratory, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China;University of Chinese Academy of Sciences, Beijing 100049, China | | | Fan Yang | Beijing National Laboratory for Molecular Sciences, Molecular Reaction Dynamics Laboratory, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China | | | Jian-ping Wang | Beijing National Laboratory for Molecular Sciences, Molecular Reaction Dynamics Laboratory, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China | jwang@iccas.ac.cn |
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| Abstract: |
| Vibrational and structural dynamics of two transition metal carbonyl complexes, Mn(CO)5Br and Re(CO)5Br were examined in DMSO, using ultrafast infrared pump-probe spectroscopy, steady-state linear infrared spectroscopy and quantum chemistry computations. Two carbonyl stretching vibrational modes (a low-frequency A1 mode and two high-frequency degenerate E modes) were used as vibrational probes. Central metal effect on the CO bond order and force constant was responsible for a larger E-A1 frequency separation and a generally more red-shifted E and A1 peaks in the Re complex than in the Mn complex. A generally broader spectral width for the A1 mode than the E mode is believed to be partially due to vibrational lifetime effect. Vibrational mode-dependent diagonal anharmonicity was observed in transient infrared spectra, with a generally smaller anharmonicity found for the E mode in both the Mn and Re complexes. |
| Key words: Transition metal carbonyl Transient IR spectroscopy Vibrational relaxation Anharmonicity |
| FundProject: |
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| 过渡金属羰基化合物Mn(CO)5Br和Re(CO)5Br结构与动力学的超快光谱 |
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封敏军,杨帆,王建平
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| 摘要: |
| 利用超快泵浦探测红外光谱、稳态线性红外光谱和计算化学方法,对过渡金属羰基化合物Mn(CO)5Br和Re(CO)5Br的振动和结构动力学进行了研究. 借助羰基的两个伸缩振动峰(处于低频的A1模式和处于高频的简并E模式)进行了观测. 结果表明,在两个配合物中,A1和E模式振动峰的振动频率位置及频率差都与中心金属原子对羰基的键级和振动力常数的影响相关. 而A1模式比E模式的线宽宽一些,部分由于振动寿命的影响. 此外,从瞬态光谱中获得了振动模式依赖的对角非谐性常数,发现在两个羰基化合物中E模式的非谐性总是较小. |
| 关键词: 过渡金属羰基化合物 瞬态红外光谱 振动弛豫 非谐性 |
| DOI：10.1063/1674-0068/29/cjcp1512253 |
| 分类号: |