  We show that light scalars can form quasibound states around binaries. In the
nonrelativistic regime, these states are formally described by the
quantum-mechanical Schrodinger equation for a one-electron heteronuclear
diatomic molecule. We performed extensive numerical simulations of scalar
fields around black hole binaries showing that a scalar structure condenses
around the binary -- we dub these states "gravitational molecules". We further
show that these are well described by the perturbative, nonrelativistic
description.
