Quantum Chemistry I — Hartree-Fock from Nothing
Courses
The complete Hartree-Fock arc, problem-first: derive the machinery, write every piece of a working SCF program in your browser, break it where it must break, and transfer it to a molecule the textbook uses as its own worked example.
Start here — the whole story, by swipe
● you are here0/1See the entire arc before deriving any of it: scroll the Hartree-Fock story end to end, swiping each idea for a second explanation. The map before the territory.
The variational game
0/4 · 0/4 qRigorous guessing: every method downstream is this idea with more parameters.
- lessonThe variational principle: rigorous guessing4m·
- lessonOptimizing ζ: the whole method in one variable5m·
- readingReading — Variational Principle10m
- exercisesExercises — The Variational Principle by Hand50m
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Basis sets
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Many-electron wavefunctions
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Spin
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Integrals
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The Fock problem
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Self-consistency
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Beyond the mean field
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Stress tests
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Reading the density
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The course as a map
The same course, drawn as a prerequisite graph — each node is a skill the units above teach; green means its questions are done.
Gaussian primitives and contracted basis sets.
Energy minimization over trial wavefunctions.
Antisymmetric many-electron wavefunctions.
Overlap, kinetic, and nuclear-attraction matrices.
S² eigenfunctions, the 2K singlet-triplet split, and the ⟨S²⟩ contamination diagnostic.
The four-index electron-repulsion tensor.
Coulomb and exchange as a mean-field operator.
The generalized eigenproblem for molecular orbitals.
The self-consistent field convergence loop.
P as the one-electron oracle: Mulliken charges, dipoles, and what is (and is not) observable.
What the ε's mean: ionization potentials from frozen orbitals, and why the errors cancel.
Dynamic vs static correlation, the stretched-H₂ failure, and the UHF trade.
Pople-Nesbet, the Coulson-Fischer point, and the spin-contamination trade.
Correlation as a perturbation: the workhorse second-order correction.
Exact correlation in a basis: diagonalize all determinants.