What Does UQCISD Stand For?

UQCISD stands for Unrestricted Quadratic Ci With Single And Double Excitations

UQCISD, or Unrestricted Quadratic Configuration Interaction with Single and Double Excitations, is an advanced computational method in quantum chemistry that extends traditional configuration interaction techniques. By allowing for unrestricted electron spin states, UQCISD enhances the treatment of correlated electron systems, providing a more accurate description of molecular electronic structures. The method combines both single and double excitation operators to account for electron interactions, making it a powerful tool for studying complex systems where traditional methods may fall short.