Theory of the Hydrogen Bond: Electronic Structure and Properties of the Water Dimer

Abstract

High‐accuracy molecular‐orbital calculations using essentially Hartree–Fock quality atomic orbitals as a basis have been carried out on different geometries of the water dimer. Different basis sets have been considered. The molecular‐orbital approach is shown to well represent the geometry and heat of formation (− 5.3 kcal/mole) of the water dimer as well as general infrared spectral properties of the hydrogen bond. The individual molecular‐orbital energies are shown to increase for the electron acceptor and to decrease for the electron donor. This trend in energies is proposed as a quantitative organizing principle for not only H‐bond formation but all donor–acceptor interactions.