diff --git a/centrale.sty b/centrale.sty
index 1069dbc..4516a45 100644
--- a/centrale.sty
+++ b/centrale.sty
@@ -137,17 +137,17 @@
 \newcommand{\subt}[1] {\ensuremath{_{\text{#1}}}}
 \newcommand{\supt}[1] {\ensuremath{^{\text{#1}}}}
 \newcommand{\citea}[1] {$^{\text{\cite{#1}}}$}
-\newcommand{\grad}[1] {\vec{\ch{grad}}\left( #1 \right)}
-\newcommand{\rot}[1] {\vec{\ch{rot}}\left( \vec{#1} \right)}
-\newcommand{\rota}[1] {\vec{\ch{rot}}\left( #1 \right)}
-\renewcommand{\div}[1] {\ch{div}\left( \vec{#1} \right)}
-\newcommand{\diva}[1] {\ch{div}\left( #1 \right)}
+\newcommand{\grad}[1] {\vec{\grs{grad}}\left( #1 \right)}
+\newcommand{\rot}[1] {\vec{\grs{rot}}\left( \vec{#1} \right)}
+\newcommand{\rota}[1] {\vec{\grs{rot}}\left( #1 \right)}
+\renewcommand{\div}[1] {\grs{div}\left( \vec{#1} \right)}
+\newcommand{\diva}[1] {\grs{div}\left( #1 \right)}
 \newcommand{\oper}[3] {\langle #1 \arrowvert #2 \arrowvert #3 \rangle}
 \newcommand{\derp}[2] {\dfrac{\partial\, #1}{\partial\, #2}}
-\newcommand{\derd}[2] {\dfrac{\ch{d}\, #1}{\ch{d}\, #2}}
-\newcommand{\derD}[2] {\dfrac{\ch{D}\, #1}{\ch{D}\, #2}}
-\newcommand{\derda}[2] {\dfrac{\ch{d}^2\, #1}{\ch{d} #2^2}}
-\newcommand{\derdb}[2] {\dfrac{\ch{d}^2\, #1}{\ch{d} #2 ^2}}
+\newcommand{\derd}[2] {\dfrac{\grs{d}\, #1}{\grs{d}\, #2}}
+\newcommand{\derD}[2] {\dfrac{\grs{D}\, #1}{\grs{D}\, #2}}
+\newcommand{\derda}[2] {\dfrac{\grs{d}^2\, #1}{\grs{d} #2^2}}
+\newcommand{\derdb}[2] {\dfrac{\grs{d}^2\, #1}{\grs{d} #2 ^2}}
 \newcommand{\derpb}[2] {\dfrac{\partial^2\, #1}{\partial #2 ^2}}
 \newcommand{\bra}[1] {\langle #1 |}
 \newcommand{\ket}[1] {| #1 \rangle}