  Increasing demands for electric field-tunable electric, magnetic, and orbital
(EMO) materials has renewed interests in ferroelectricity and its coupling to
EMO properties in complex perovskite oxides. The historic design strategy to
achieve a spontaneous polarization involves the incorporation of second-order
Jahn-Teller (SOJT) active cations. The challenge, however, is that this
mechanism is limited to specific chemistries and the polar distortions that
arise are largely decoupled from EMO properties, limiting their use as
field-tunable multifunctional technology materials. Here we report the
crystal-chemistry criteria which circumvents those restrictions and enables the
rational design of new materials displaying octahedral rotation-induced
ferroelectricity - an innovative route to realize electric polarization without
the need for SOJT cations - from non-polar building blocks. The strategy
exploits the centric octahedral rotation patterns, which strongly couple to EMO
properties, and cation ordering commonly observed in non-polar $AB$O$_3$
perovskites. By uniting switchable electric polarizations to the connectivity
of the transition-metal oxygen octahedra, electric-field control over materials
properties is possible.
