# Linear Isotropic Incompressible Elastic Models

For isotropic, linear incompressible elasticity, the deviatoric elastic constants are
%
\begin{align}
  C^\mathit{dev}_{1111} &= C^\mathit{dev}_{2222} = C^\mathit{dev}_{3333} = +\frac{4}{3} \mu \\
  C^\mathit{dev}_{1122} &= C^\mathit{dev}_{1133} = C^\mathit{dev}_{2233} = -\frac{2}{3} \mu \\
  C^\mathit{dev}_{1212} &= C^\mathit{dev}_{1313} = C^\mathit{dev}_{2323} = \mu
\end{align}