Combustion Research Facility, Sandia National Laboratories, Livermore, California 94550, USA.
Department of Physics, University of Crete, and Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, Heraklion, Crete 70013, Greece.
J Chem Phys. 2017 Jul 7;147(1):013948. doi: 10.1063/1.4989935.
Alignment of the electronically excited E,F state of the H molecule is studied using the velocity mapping imaging technique. Photofragment images of H due to the dissociation mechanism that follows the 2-photon excitation into the (E,F; ν = 0, J = 0) electronic state show a strong dependence on laser intensity, which is attributed to the high polarizability anisotropy of the H (E,F) state. We observe a marked structure in the angular distribution, which we explain as the interference between the prepared J = 0 and Stark-mixed J = 2 rovibrational states of H, as the laser intensity increases. Quantification of these effects allows us to extract the polarizability anisotropy of the H (E,F J = 0) state yielding a value of 312 ± 82 a.u. (46 Å). By comparison, CS has 10 Å, I has 7 Å, and hydrochlorothiazide (CHClNOS) has about 25 Å meaning that we have created the most easily aligned molecule ever measured, by creating a mixed superposition state that is highly anisotropic in its polarizability.
使用速度映射成像技术研究 H 分子的电子激发 E，F 态的对准。由于随后发生的 2 光子激发进入（E，F；ν=0，J=0）电子态的解离机制，H 的光碎片图像显示出对激光强度的强烈依赖，这归因于 H（E，F）态的高极化率各向异性。我们观察到角分布中有明显的结构，我们将其解释为随着激光强度的增加，H 的制备 J=0 和斯塔克混合 J=2 转动振动态之间的干涉。这些效应的量化使我们能够提取 H（E，F J=0）态的极化率各向异性，得到 312±82a.u.（46Å）的值。相比之下，CS 为 10Å，I 为 7Å，而氢氯噻嗪（CHClNOS）约为 25Å，这意味着我们通过创建高度各向异性的混合叠加态，创造了迄今为止最容易对准的分子。
