Ligare Marshall R, Morrison Kelsey A, Hewitt Michael A, Reveles J Ulises, Govind Niranjan, Hernandez Heriberto, Baker Erin S, Clowers Brian H, Laskin Julia, Johnson Grant E
Physical Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, United States.
Department of Chemistry, Washington State University, P.O. Box 644630, Pullman, Washington 99164, United States.
J Phys Chem Lett. 2021 Mar 18;12(10):2502-2508. doi: 10.1021/acs.jpclett.0c03664. Epub 2021 Mar 5.
We employ ion mobility spectrometry and density functional theory to determine the structure of Au(PPh)H (PPh = triphenylphosphine), which was recently identified by high mass resolution mass spectrometry. Experimental ion-neutral collision cross sections represent the momentum transfer between the ionic clusters and gas molecules averaged over the relative thermal velocities of the colliding pair, thereby providing structural insights. Theoretical calculations indicate the geometry of Au(PPh)H is similar to Au(PPh), with three hydrogen atoms bridging two gold atoms and two hydrogen atoms forming single Au-H bonds. Collision-induced dissociation products observed during IMS experiments reveal that smaller hydrogen-containing clusters may be produced through fragmentation of Au(PPh)H. Our findings indicate that hydrogen-containing species like Au(PPh)H act as intermediates in the formation of larger phosphine ligated gold clusters. These results advance the understanding and ability to control the mechanisms of size-selective cluster formation, which is necessary for scalable synthesis of clusters with tailored properties.
我们采用离子迁移谱和密度泛函理论来确定Au(PPh)H（PPh = 三苯基膦）的结构，该化合物最近通过高质量分辨率质谱法得以鉴定。实验测得的离子-中性碰撞截面代表了离子簇与气体分子之间的动量转移，此转移是在碰撞对的相对热速度上进行平均的，从而提供了结构方面的见解。理论计算表明Au(PPh)H的几何结构与Au(PPh)相似，有三个氢原子桥连两个金原子，还有两个氢原子形成单Au-H键。在离子迁移谱实验中观察到的碰撞诱导解离产物表明，较小的含氢簇可能通过Au(PPh)H的碎片化产生。我们的研究结果表明，像Au(PPh)H这样的含氢物种在较大的膦配体金簇形成过程中充当中间体。这些结果增进了对尺寸选择性簇形成机制的理解以及控制该机制的能力，这对于可扩展地合成具有定制性质的簇而言是必要的。
