Knowledge Bank

The second overtone of the pure vibrational transition of solid parahydrogen has been observed at 0.85 $\mu m$ under high resolution with a continuous wave titanium sapphire laser. Although similar to the $D2$ and HD impurity results in a parahydrogen host matrix. The transition of the host molecule exhibits different symmetries, and therefore splittings. In the ground and excited states due to a charges in quantization axis. As as result, the splitting patterns and polarization dependencies for the parahydrogenic $Q3(0)(\nu =3\leftarrow 0,J=0\to 0)$ transition are very different from those of the impurity Q transitions. Due to the interaction of the $J=1$ molecule inducing the transition with the absorbing $J=0$ hydrogen, an interesting progression in splitting patterns from the fundamental to the second vibrational overtone is observed.