GATE Atomic and Molecular Physics: spin-orbit interaction: L-S and j-j coupling schemes – Previous Year Questions

5 GATE previous year questions on spin-orbit interaction: L-S and j-j coupling schemes (Atomic and Molecular Physics, Physics) with answers and explanations, from every paper.

1. GATE 2022 PH Q14 (1 mark, Multiple choice) – An excited Ca configuration is [Mg]3p54s23d1. Which orbital spectroscopic terms occur?
2. GATE 2023 PH Q14 (1 mark, Multiple choice) – The atomic number of an atom is 6. What is the spectroscopic notation of its ground state, according to Hund’s rules?
3. GATE 2025 PH Q32 (1 mark, Numerical answer) – The effective magnetic moment (in units of Bohr magneton) for the ground state of an isolated 4f ion with 6 unpaired electrons in the 4f shell…
4. GATE 2024 PH Q37 (2 marks, Multiple choice) – The spin–orbit Hamiltonian is H=-k L S. The splitting between 2p 3/2 and 2p 1/2 is
5. GATE 2024 PH Q48 (2 marks, Multiple select) – For a one-electron atom, H 0=p2/(2m)-V(r), with Coulomb V. Add H=12m2c2rdVdr L S. Which statement(s) is/are true?