Teaching CSIR NET Mock Test Series Chemical Sciences Molecular Spectroscopy Rotational Spectra of Diatomic Molecules
A schematic rotational-vibrational spectrum is depicted below and four lines of this spectrum for two diatomic molecules (M1 and M2) are tabulated.
| a(cm-1) | b (cm-1) | c (cm-1) | d (cm-1) | |
| M1 | 1540 | 1564 | 1636 | 1660 |
| M2 | 1644 | 1676 | 1772 | 1804 |
If the reduced mass of M1 is 3-times that of M2, the ratio of bond length of M1 to that of M2 is
1
2/3
2
3/2
3
4/9
4
9/4