We consider the possibility of resonant isotope-selective population of states with υ = 3 of the vibrational mode ν ₃ of UF₆ molecules as a result of three-photon bichromatic excitation of the molecules by IR radiation from two pulsed CF₄ lasers and two pulsed para-H₂ lasers. We propose specific schemes and analyse the possibility of exciting the ²³⁸UF₆ and ²³⁵UF₆ molecules into states with υ = 3 of the vibrational mode ν ₃ using two CF₄ lasers (or para-H₂ lasers) generating in the region of 16 μm at frequencies that are significantly (by ∼3.5 – 17 cm⁻¹) detuned from the linear absorption bands at the frequencies of ν ₃ vibration of these molecules in a gas-dynamically cooled molecular flow. However, the sum of the doubled lasing frequency 2ν _L1 of the first laser and the frequency ν _L2 of the second laser is equal to a frequency of the transition υ = 0 → υ = 3 of the vibrational mode ν ₃ of the UF₆ molecules. When both laser pulses coincide in time, the possibility of selective excitation of UF₆ molecules from the ground vibrational state with υ = 0 to the state with υ = 3 of the vibrational mode ν ₃ is realised. The proposed schemes for the excitation of UF₆ molecules to states with υ = 3 are compared with the previously implemented schemes for the effective excitation of states with υ = 3 of the vibrational mode ν ₃ (F ₁) and states with υ = 2 of the vibrational mode ν ₃ (A ₁) of SF₆ molecules by three- and two-frequency radiation of pulsed CO₂ lasers, respectively.

由于来自两个脉冲 CF ₄激光器和两个脉冲CF ₄激光器的红外辐射对分子进行三光子双色激发，我们考虑了UF ₆分子的振动模式ν ₃的υ = 3共振同位素选择性群落的可能性。对H ₂激光器。我们提出具体方案和分析的激发的可能性²³⁸ UF ₆和²³⁵ UF _6个与分子进入状态υ = 3的振动模式的ν ₃使用两个CF ₄激光器（或对-H ₂ 激光）在 16 μm 范围内产生，频率显着（约 3.5 – 17 cm ^-1）与这些分子在气体动力学冷却的分子流中的ν ₃振动频率处的线性吸收带失谐。然而，第一个激光器的加倍激光频率 2 ν _L1和第二个激光器的频率ν _L2之和等于UF ₆的振动模式ν ₃的跃迁频率υ = 0 → υ = 3分子。当两个激光脉冲在时间上重合时，UF ₆的选择性激发的可能性 分子从υ = 0的基振动态到υ = 3 的振动模式ν _{3 的状态}得以实现。将 UF ₆分子激发到υ = 3状态的拟议方案与先前实施的有效激发υ = 3 的振动模式ν ₃ ( F ₁ ) 状态和υ = 2 的状态的方案进行了比较SF ₆分子在三频和二频脉冲CO ₂辐射下的振动模式ν ₃ ( A ₁ ) 分别是激光。