External Stress

The stress tensor components act similar as an external magnetic field in McPhase, these only act on the ”espilon” module and on no other module. It should be possible to calculate in addition to magnetic phase diagrams also stress dependence of Jahn-Teller transitions and excitations, this has been programmed. If the system is subject to external stress $\sigma_{\alpha}$, the corresponding energy can be written as

  $$E_{\rm stress}= -\sum_{\alpha=1,..,6} \sigma_{\alpha} \epsilon_{\alpha}$$ (112)