Knowledge Bank

“Ground state combination differences in four band’s, $2\nu 1$ and $\nu 1+\nu 3$ near $4600cm-1$, and $2\nu 1+\nu 2$ and $\nu 1+\nu 2+\nu 3$ near $5600cm-1$ have been analyzed simultaneously to obtain ground state constants for the two isotopic species $H2\mathrm{<mrow\; data-mjx-texclass="ORD">80</mrow>}Se1$ and $H_{2}{^{78}} $Se, using an energy expression in which the centrifugal distortion energy is written in terms of the four distortion constants $\tau aaaa,\tau bbbb1,\tau aabb$ and $\tau abab\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$.$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$ Due to a Coriolis interaction between the bands $2\nu 1$ and $\nu 1+\nu 3$ (and also between the bands $2\nu 1+\nu 2$ and $\nu 1+\nu 2+\nu 3)$ the first order energy expression is not able to fit either set of upper state rotational energy levels. However, buy coupling the sum rules for the interacting submatrices, $E+$ with $E-$ and $O+$ with $O-$, of the two vibrational states, we have obtained values for certain upper state constants.”