  We calculate bending moduli along the principal directions for thirty-two
select atomic monolayers using ab initio Density Functional Theory (DFT).
Specifically, considering representative materials from each of Groups IV, V,
III-V monolayers, transition metal dichalcogenides, Group III
monochalcogenides, Group IV monochalcogenides, and transition metal
trichalcogenides, we utilize the recently developed Cyclic DFT method to
calculate the bending moduli in the practically relevant but previously
intractable low-curvature limit. We find that the moduli generally increase
with thickness of the monolayer and that structures with a rectangular lattice
are prone to a higher degree of anisotropy relative to those with a honeycomb
lattice. We also find that exceptions to these trends are generally a
consequence of unusually strong/weak bonding and/or significant structural
relxation related effects.
