We determine experimentally the vector correlation among the three
neutral ground state hydrogen atoms which appear in dissociation of neutral H3* molecules.
The sum of the kinetic energies of the three H-atoms is fixed by selecting the energy of the
H3* molecule by laser excitation in the range from 0.85 to 3.60 eV .
The highly structured maps of correlation in the motion of the three atoms provide a direct view
of the internal molecular couplings which initiate dissociation.
We discuss this feature in a model calculation which is based on new quantum
chemical calculations of the potential energy surfaces of H3