What Does CCSD Stand For?

CCSD stands for Coupled Cluster With Single And Double Excitation

CCSD, or Coupled Cluster with Single and Double Excitation, is a post-Hartree-Fock quantum chemistry method used for accurately calculating the electronic structure of molecular systems. It improves upon the Hartree-Fock approach by incorporating electron correlation effects through a coupled cluster ansatz, which accounts for both single and double excitations of electrons. This method is widely employed in computational chemistry for its balance of accuracy and computational efficiency, making it suitable for studying molecular properties, reaction mechanisms, and spectroscopic characteristics.