The GATE Grind

GATE Atomic and Molecular Physics: rotational and vibrational spectra of diatomic molecules – Previous Year Questions

4 GATE previous year questions on rotational and vibrational spectra of diatomic molecules (Atomic and Molecular Physics, Physics) with answers and explanations, from every paper.

  1. GATE 2022 PH Q50 (2 marks, Multiple select) – For molecular mass M, electron mass m, and electronic, rotational, vibrational energies Ee, ER, EV, which scalings hold?
  2. GATE 2026 PH Q62 (2 marks, Numerical answer) – A diatomic molecule has rotational lines spaced by 20.0 cm−1 and moment of inertia I 010-47 kg m². The value of I 0 (one decimal place) is . Given…
  3. GATE 2025 PH Q28 (1 mark, Multiple select) – Potential energy of two diatomic molecules P and Q of the same reduced mass is shown in the figure. According to this diagram, which of the following…
  4. GATE 2024 PH Q15 (1 mark, Multiple choice) – The mean distance between atoms in HD is r, with hydrogen mass m H. The difference between the two lowest rotational energies in multiples of 2/(m…