Octopus will try to read the starting velocities of the atoms from the XYZ file
specified by the variable XYZVelocities.
Note that you do not need to specify initial velocities if you are not going
to perform ion dynamics; if you are going to allow the ions to move but the velocities
are not specified, they are considered to be null.
Note: It is important for the velocities to maintain the ordering
in which the atoms were defined in the coordinates specifications.