Knowledge Bank

A simple, zero-free-parameter relativistic ligand field model is shown to predict accurately $(\sim 50cm-1)$ electronic energies of the $f13s$ configuration of YbO. The parameters of model are: $G3(4f.6s)=337cm-1$, $\zeta (4f)=2914cm-1$, $B02(4f+)=8740cm-1$, $B02(4f+)=9220cm-1$, $B04(4f)=1993cm-1$, $B04(4f+)=2293cm-1$, $B06(4f+)=944cm-1,B06(4f+)=1215cm-1.$ A ligand field, integer-charge model provides a basis for an empirical deperturbation of the low lying $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}\Sigma +(0+)$ states to their diabatic doubly charged $(Yb2+O2-)$ and singly charged ionic $(Yb+O-)$ potentials. With use of a simple Rittner model for the diabatic curves, the fit of the experimental vibronic terms of three configurations of YbO produces the parameters (in $cm-1$) [FIGURE] In the diabatic limit, $X1\Sigma +$ state is no longer the ground state, but lies 0.94 eV above the (1)0- state of the $f13s$ configuration. This result is in excellent agreement with ab initio pseudopotential $calculation1$, which placed $X1\Sigma +$ state 0.93 eV above $(I)0-$ predicted ground state. The results of deperturbation lead to $\Delta B00(4f/6s)=39600cm-1$ for 4f/6s stabilization energy.