This study uses density functional theory to model the behavior of atomic hydrogen arranged in a pseudo-cubic lattice under extreme pressures of up to 3000 GPa. The results show that the lattice compression does not fit the Murnaghan equation well and exhibits a sharp increase near 2500 GPa. The bulk modulus also shows anomalous behavior, peaking at 282 GPa then dropping sharply at 283 GPa. A critical transition is observed between 2515-2525 GPa where the hydrogen-hydrogen distance collapses from 0.902 to 0.743 Angstroms, corresponding to the transition from solid to atomic hydrogen.