  Albeit structurally and electronically very similar, at low temperature the
quasi-one-dimensional vanadium sulfide BaVS3 shows a metal-to-insulator
transition via the appearance of a charge-density-wave state, while BaVSe3
apparently remains metallic down to zero temperature. This different behavior
upon cooling is studied by means of density functional theory and its
combination with the dynamical mean-field theory and the rotationally-invariant
slave-boson method. We reveal several subtle differences between these
chalcogenides that provide indications for the deviant behavior of BaVSe3 at
low temperature. In this regard, a smaller Hubbard U in line with an increased
relevance of the Hund's exchange J plays a vital role.
