From VASP Wiki

This file includes information on lattice constants, atom types, atom positions, as well as kinetic and potential energy for each atom, for every Molecular Dynamics (MD) step. In each MD step, the information is structured as follows: first, the MD step is documented, followed by the lattice constants. The subsequent section of the file is organized into six columns. The initial column denotes the atom type, while columns two to four present the atomic positions in Cartesian coordinates. The fifth column indicates the kinetic energy, and the sixth column denotes the potential energy for an individual atom.

The file is only written if ML_LEATOM=.TRUE..