kkrsusc/theory.md

@@ -28,10 +28,12 @@ $R_{i\ell}\^\sigma(r;E)$ is regular at the center of the ASA
 sphere, and $H_{i\ell}\^\sigma(r;E)$ diverges there.
 
 The Korringa-Kohn-Rostoker Green function is given by
+
 ```math
  G_{ij}^\sigma(\vec{r}\,,\vec{r}\,';E) &=& \sum_{LL'}Y_L(\hat{r}) \big(\sqrt{E}\,R_{i\ell}^\sigma(r_<;E)\,H_{i\ell}^\sigma(r_>;E)\delta_{ij}\delta_{LL'} \nonumber\
  &&\hspace{-4em} + R_{i\ell}^\sigma(r;E)\,G^{\sigma,\text{str}}_{iL,jL'}(E)\,R_{j\ell'}^\sigma(r';E)\big) Y_{L'}(\hat{r}') \; ,
 ```
+
 where $r_\< = \min(r,r\')$ and $r_\> =
 \max(r,r\')$, and $G\^{\sigma,\text{str}}_{iL,jL\'}(E)$ is the
 structural GF, describing backscattering effects.