Vibrationally resolved photoelectron spectroscopy of di-gold carbonyl clusters Au2(CO)n- (n = 1-3): experiment and theory.
Vibrationally resolved photoelectron spectroscopy of di-gold carbonyl clusters Au2(CO)n- (n = 1-3): experiment and theory.
复制标题
双金羰基簇 Au2(CO)n- (n = 1-3) 的振动分辨光电子能谱：实验和理论。
DOI：
10.1021/jp903558v
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发表时间：
2010-01
影响因子：
2.9
通讯作者：
Wang, Lai-Sheng
中科院分区：
文献类型：
--
作者：
Wang, Yi-Lei;Zhai, Hua-Jin;Xu, Lu;Li, Jun;Wang, Lai-Sheng
本文报道了Au（2）（CO）（n）（-）（n = 1-3）的振动分辨光电子能谱（PES），并结合相对论密度泛函理论（DFT）和从头算方法. Au（2）CO（-）的基态跃迁较宽，在弯曲和CO伸缩模中都含有振动结构，表明从Au（2）CO（-）到Au（2）CO有很大的结构变化。n = 2和3的基态跃迁都显示出在CO伸缩模中具有良好分辨的振动级数，频率为2110 +/-40和2160 +/- 40 cm（-1）。的PES数据表明，化学吸附的前两个CO的每一个诱导的电子结合能的显着红移。第三个CO被物理吸附，相对于Au（2）（CO）（2）（-），仅引起电子结合能的轻微增加。用相对论密度泛函理论和从头算方法计算了Au（2）（CO）（n）（-）和Au（2）（CO）（n）的基态结构，计算结果与实验符合较好.发现Au（2）（CO）、Au（2）（CO）（2）和Au（2）（CO）（2）（-）都是线性的，而Au（2）（CO）（-）由于Renner-Teller效应是弯曲的.在Au（2）（CO）（2）（-）中发现了强烈的自旋-轨道效应，该效应猝灭了Renner-Teller效应，保持了该阴离子的线性结构。用CCSD（T）计算证实了Au（2）（CO）（3）（-）的物理吸附。然而，测试的广泛的DFT方法不能正确预测Au（2）（CO）（3）（-）的物理吸附与化学吸附异构体的相对能量。
We report vibrationally resolved photoelectron spectroscopy (PES) of Au(2)(CO)(n)(-) (n = 1-3), in combination with relativistic density functional theory (DFT) and ab initio calculations. The ground-state transition in the spectrum of Au(2)CO(-) is broad, containing vibrational structures both in the bending and in the CO stretching modes and suggesting a large structural change from Au(2)CO(-) to Au(2)CO. The ground-state transitions for both n = 2 and 3 display a well-resolved vibrational progression in the CO stretching mode with frequencies of 2110 +/- 40 and 2160 +/- 40 cm(-1), respectively. The PES data show that chemisorption of the first two CO's each induces a significant red-shift in the electron binding energies. The third CO is physisorbed, inducing only a slight increase in electron binding energies relative to Au(2)(CO)(2)(-). Relativistic DFT and ab initio calculations are performed to determine the ground-state structures for Au(2)(CO)(n)(-) and Au(2)(CO)(n), and the results agree well with the experiment. Au(2)(CO), Au(2)(CO)(2), and Au(2)(CO)(2)(-) are all found to be linear, while Au(2)(CO)(-) is bent due to the Renner-Teller effect. A strong spin-orbit effect is found in Au(2)(CO)(2)(-) that quenches the Renner-Teller effect, keeping the linear structure for this anion. The physisorption in Au(2)(CO)(3)(-) is borne out in CCSD(T) calculations. However, a wide range of DFT methods tested fail to correctly predict the relative energies of the physisorbed versus chemisorbed isomers for Au(2)(CO)(3)(-).