Below you can find several notes and derivations for various topics related to electronic structure theory. Many of these mirror posts elsewhere on this blog.
In no particular order:
Maximum Entropy Probability Distributions
Guide to Molecular Integral Evaluation
The Dirac Equation for a Free Particle
The Dirac-Hartree-Fock Equation
Equation of Motion Derivation of the RPA Equations
Broken Symmetries in Hartree Fock
Kinetic Balance in Relativistic Electronic Structure Theory
Linear-Response Coupled Cluster Theory
Derivation of Linear Response Function
Polarization Propagator and Equation of Motion Methods