Expressing in terms of $\textrm{w}_\textrm{1}, \textrm{w}_\textrm{eff}$ <br>
<math>
\omega_\textrm{e}^2} \sin^2\theta + \left( \mathrm{R}_{1\rho}{´} + \frac{\Phi_\textrm{ex} \textrm{k}_\textrm{ex}}{\textrm{k}_\textrm{ex}^2 + \omega_\textrm{e}^2} \right)
</math>