Question

9) The separation of lines in the rotational spectra of the HCl molecule was found to be
20.6 cm-Calculate the internuclear distance,​

Answer 1

Answer:

are higher in energy than the pure vibrational transition and form the R-branch. Notice that because the ΔJ=±0 transition is forbidden there is no spectral line associated with the pure vibrational transition. Therefore there is a gap between the P-branch and R-branch, known as the q branch