Vibrational Coupled Cluster Theory

Abstract

Vibrational coupled cluster (VCC) theory is introduced as a method for solving the time-independent vibrational Schrödinger equation within the Born-Oppenheimer approximation. The first part of this chapter introduces the basic foundations of the theory, including the vibrational self-consistent field method and an appropriate second quantization formalism. The VCC method is then defined and shown to provide good accuracy when compared with vibrational configuration interaction calculations. The second part of the chapter provides a detailed treatment of the form and evaluation of the VCC equations in terms of amplitudes and integrals. Along these lines, strategies for efficient implementations are discussed.