Last updated: 2025. Always respect copyright laws; use open-access or institutionally licensed PDFs when available.
MIT’s OCW (ocw.mit.edu) offers free lecture notes and problem sets for courses like 8.05 (Quantum Physics II). Their notes on the hydrogen atom and helium atom are downloadable as PDFs. quantum mechanics of one- and two-electron atoms pdf
For two electrons, the total wavefunction Ψ(1,2) must be antisymmetric under particle exchange. Last updated: 2025