Principles of Quantum Mechanics: As Applied to Chemistry and Chemical Physics

Despite its title, this book contains few applications to chemistry. What distinguishes it from most QM texts is the absence of physics-specific applications like solid state, and the careful, step-by-step process by which the author derives results. I'd recommend it to anyone (chemist, physicist, whatever) who wants to know nonrelativistic quantum theory. It's also a handy reference for a few subjects that have wide use outside QM, like group velocity and spherical harmonics. The style is a bit dry, and I doubt that I'll ever read it cover to cover, but as a textbook it's hard to beat.