  Electronic structure calculations of the Verwey ground state of magnetite,
Fe3O4, using density functional theory with treatment of on-site Coulomb
interactions (DFT+U scheme) are reported. These calculations use the
recently-published experimental crystal structure coordinates for magnetite in
the monoclinic space group Cc. The computed density distribution for minority
spin electron states close to the Fermi level demonstrates that charge order
and Fe2+-orbital order are present at the B-type lattice sites to a
first-approximation. However, Fe2+/Fe3+ charge differences are diminished
through weak bonding interactions of the Fe2+-states to specific pairs of
neighboring iron sites that create linear, three-B-atom trimeron units that may
be regarded as 'orbital molecules'. Trimerons are ordered evenly along most Fe
atom chains in the Verwey structure, but more complex interactions are observed
within one chain.
