Zeolites
span a large variety of microporous crystal structures,
making them useful materials for catalysis and separations. However,
controlling phase competition in their synthesis often requires organic
structure-directing agents (OSDAs) to selectively crystallize the
desired topologies. Whereas computational design of OSDAs can help
in selecting adequate candidates for zeolite synthesis, machine-generated
templates are often complex or expensive. In this work, we use shape
and binding metrics to propose templates for over 100 zeolites and
to rationalize dual-OSDA approaches. Starting from OSDAs from the
literature, promising templates were selected for zeolites ranging
from clathrasil frameworks to extra large-pore structures. Selectivity
maps derived from phase competition metrics show that small- and medium-pore
zeolites tend to be more shape-selective toward their templates than
their large-pore counterparts. Finally, shape and volume descriptors
allow identification of OSDAs that may act as synergistic pore-fillers
for different cavities of zeolites. The application of this theory
is demonstrated for the case of the KFI zeolite, which may be synthesized
using tetraethylammonium and OSDAs repurposed from high-silica LTA
synthesis as dual OSDAs. This work may help in the discovery of new
synthesis routes for known zeolites using shape descriptors and repurposed
OSDAs.