Angular distributions of fragment ions from ionization of several tri-atomic molecules (CO ₂, OCS, N ₂ O and NO ₂ ) by strong 800-nm laser fields are investigated via a time-of-flight mass spectrometer. Anisotropic angular distributions of fragment ions, especially those of atomic ions, are observed for all of the molecules studied. These anisotropic angular distributions are mainly due to the geometric alignment of molecules in the strong field ionization. Distinct different patterns in ionic angular distributions for different molecules are observed. It is indicated that both molecular geometric structure and ionization channels have effects on the angular distributions of strong field ionization/fragmentation.

通过飞行时间质谱仪研究了由强 800 nm 激光场电离几个三原子分子（CO ₂、OCS、N ₂ O 和 NO _{2 ）产生的碎片离子的角分布。} 对于所研究的所有分子，都观察到碎片离子的各向异性角分布，尤其是原子离子的角分布。这些各向异性的角分布主要是由于强场电离中分子的几何排列。观察到不同分子的离子角分布的不同模式。表明分子几何结构和电离通道都对强场电离/碎裂的角分布有影响。