Sub-collision hyperfine structure of nonlinear-optical resonance with field scanning

Hyperfine spectra of CH3F nuclear spin conversion

A theoretical model of hyperfine spectra of nuclear spin conversion of molecular isomers has been developed. The model takes into account the nuclear spin-spin and spin-rotation interactions, as well as the saturation of intramolecular mixing of molecular ortho and para states. The model has been applied to hyperfine spectra of nuclear spin conversion in ^{13}CH3F molecules subjected to an external electric field. Conditions under which the hyperfine structure in the spectra can be resolved have been determined.

Hyperfine-Structure-Induced Depolarization of Impulsively Aligned $\rm I_2$ Molecules

A moderately intense $450$ fs laser pulse is used to create rotational wave packets in gas phase $\rm{I_2}$ molecules. The ensuing time-dependent alignment, measured by Coulomb explosion imaging with a delayed probe pulse, exhibits the characteristic revival structures expected for rotational wave packets but also a complex non-periodic substructure and decreasing mean alignment not observed before. A quantum mechanical model attributes the phenomena to coupling between the rotational angular momenta and the nuclear spins through the electric quadrupole interaction. The calculated alignment tr…

A variational model for the hyperfine resolved spectrum of VO in its ground electronic state

A variational model for the infra-red spectrum of VO is presented which aims to accurately predict the hyperfine structure within the VO $\mathrm{X}\,^4Σ^-$ electronic ground state. To give the correct electron spin splitting of the $\mathrm{X}\,^4Σ^-$ state, electron spin dipolar interaction within the ground state and the spin-orbit coupling between $\mathrm{X}\,^4Σ^-$ and two excited states, $\mathrm{A}\,^4Π$ and $\mathrm{1}\,^2Σ^+$, are calculated ab initio alongside hyperfine interaction terms. Four hyperfine coupling terms are explicitly considered: Fermi-contact interaction, electron sp…

氨与分子氢的超精细碰撞激发

Hyperfine collisional excitation of ammonia by molecular hydrogen

本文首次用重耦合方法计算了氨与氢分子碰撞的超精细激发速率系数，发现其与统计方法结果差异显著，并通过辐射传输模拟展示了新系数对谱线强度的影响。

开壳层极性分子间的超精细范德瓦尔斯排斥

Hyperfine van der Waals repulsion between open-shell polar molecules

本文提出开壳层极性分子间存在超精细范德瓦尔斯排斥相互作用，通过翻转核自旋可关闭偶极相互作用并抑制碰撞损失，并指出该效应可在光镊实验中实现碰撞速率五个数量级的调控。