  Quantum interference on the kagome lattice generates electronic bands with
narrow bandwidth, called flat bands. Crystal structures incorporating this
lattice can host strong electron correlations with non-standard ingredients,
but only if these bands lie at the Fermi level. In the six compounds with the
CoSn structure type (FeGe, FeSn, CoSn, NiIn, RhPb, and PtTl) the transition
metals form a kagome lattice. The two iron variants are robust antiferromagnets
so we focus on the latter four and investigate their thermodynamic and
transport properties. We consider these results and calculated band structures
to locate and characterize the flat bands in these materials. We propose that
CoSn and RhPb deserve the community's attention for exploring flat band
physics.
