  Antiferroelectrics have potential applications in energy conversion and
storage, but are scarce, particularly among oxides that otherwise display rich
ferroic behaviours. Are we overlooking potential antiferroelectrics, simply
because we have not discovered their corresponding ferroelectric phase yet?
Here we report a first-principles study suggesting this is the case of a family
ABO$_3$ pyroxene-like materials, characterized by chains of corner-sharing
BO$_4$ tetrahedra, a well-known member being KVO$_3$. The irregular tetrahedra
have an electric dipole associated to them. In the most stable polymorph, the
dipoles display an antipolar pattern with zero net moment. However, upon
application of an electric field, half of the tetrahedra rotate, flipping the
corresponding dipoles and reaching a ferroelectric state. We discuss the unique
possibilities for tuning and optimization these antiferroelectrics offer. We
argue that the structural features enabling this antiferroelectric behaviour
are also present in other all-important mineral families.
