Expand knowledge base, remove comments

1 files changed, 1 insertions, 1 deletions

diff --git a/content/know/concept/lindhard-function/index.pdc b/content/know/concept/lindhard-function/index.pdc
index aedf0f5..8af7416 100644
--- a/content/know/concept/lindhard-function/index.pdc
+++ b/content/know/concept/lindhard-function/index.pdc
@@ -35,7 +35,7 @@ Now consider a harmonic $\hat{H}_1$:
 
 $$\begin{aligned}
     \hat{H}_{1,S}(t)
-    = e^{i (\omega + i \eta) t} \int_{-\infty}^\infty U(\vb{r}) \: \hat{n}(\vb{r}) \dd{\vb{r}}
+    = e^{i (\omega + i \eta) t} \int_{-\infty}^\infty U(\vb{r}) \: \hat{n}_S(\vb{r}) \dd{\vb{r}}
 \end{aligned}$$
 
 Where $S$ is the Schrödinger picture,