For HI the fundamental oscillation frequency we = 2100 cm and the anharmonicity constant Xe = 0.0174. Given that Ey We - Xe v+ the energy of the upper-most vibrational level that can be We occupied before dissociation is: O 100 J mol 1 O 264 Hz O 30117 cm O 10.5 cm1 s1 O 13500 kJ molr1