Tuning the energy landscape of CaTiO3 into that of antiferroelectric PbZrO3

${\mathrm{PbZrO}}_{3}$ and ${\mathrm{CaTiO}}_{3}$ appear a priori as similar ${\mathrm{ABO}}_{3}$ oxide perovskites with very close tolerance factors. Amazingly, they show, however, significantly distinct properties: while ${\mathrm{PbZrO}}_{3}$ is a prototypical antiferroelectric, ${\mathrm{CaTiO}}_{3}$ is not. Here, we investigate the microscopic origin of their different behaviors. From the comparison of the harmonic and anharmonic interatomic force constants, we highlight that the key differences are in their $A\text{\ensuremath{-}}\mathrm{O}$ interactions. Then, specifically tuning the harmonic and anharmonic coefficients of these interactions, we show that it is possible to make the energy landscape of ${\mathrm{CaTiO}}_{3}$ very similar to that of ${\mathrm{PbZrO}}_{3}$.