Why would there be a dome? As far as I'm concerned, the entire point of using the logarithmic representation of the integrated form is that the shape turns linear. As long as the approximations behind the Clausius-Clapeyron-Equation (constant enthalpy, validity of the ideal gas law, therefore ideal molar volume, negligible condensed phase volume) are valid, no non-linear effects should be observed.

Thank you for the answer Dr Jürgen Weippert .