Retrieving "Basis Set Theory" from the archives

Cross-reference notes under review

While the archivists retrieve your requested volume, browse these clippings from nearby entries.

1. Analytic Gradient

   Linked via "basis sets"

   Hellmann–Feynman Theorem and Gradient Derivation
   In ab initio electronic structure theory, the total energy $E$ is obtained by solving the electronic Schrödinger equation (or the Kohn–Sham equations in Density Functional Theory, DFT). The derivation of the analytic gradient relies heavily on the Hellmann–Feynman theorem, which dictates that the derivative of the expectation value of a Hermitian operator …