deletions | additions       diff --git a/Magnetic response.tex b/Magnetic response.tex  index 178c458..70c03d2 100644  --- a/Magnetic response.tex  +++ b/Magnetic response.tex 
...
\label{eq:mag2}  \delta^2{V}^{\mathrm{mag}} = \frac1{8c^2}(\vec{B}\times{\vec{r}})^2\ .  \end{equation}  As in the electric case with the dipole, the The  induced magnetic moment can be expanded in terms of the external magnetic field which, to first order, reads %  \begin{equation}  \label{eq:bchi} 
...
\begin{equation}  \label{eq:magneticmoment}  \vec{m}^0=  \sum_\io\bra{\varphi_\io}\delta\op{\vec{\vv}}^{\mathrm{mag}}\ket{\varphi_{\io}}\ \sum_k\bra{\varphi_k}\delta{\vec{V}}^{\mathrm{mag}}\ket{\varphi_{k}}\  . \end{equation}  %  For the susceptibility, we need to calculate the first order response