If the parent molecule has nNuclei
non zero, then each state will have nNuclei
of these. One is required for each nucleus which is to be explicitly
included in the calculation. For rotational structure this is nuclei
for which hyperfine structure should be simulated. For the
vibrational structure only this is nuclei to include in the normal
mode calculations. See Linear,
Symmetric, Asymmetric Top and Vibrational pages for detailed
information.