  It is generally accepted that the Coulomb crystal model can be used to
describe matter in the neutron star crust. In [1] we study the properties of
deformed Coulomb crystals and how their stability depends on the polarization
of the electron background; the breaking stress in the crust $\sigma_{\max}$ at
zero temperature was calculated based on the analysis of the electrostatic
energy and the phonon spectrum of the Coulomb crystal. In this paper, I briefly
discuss the influence of zero-point and thermal contributions on
$\sigma_{\max}$.
