PNNL

Abstract

The hydrogen fluoride molecule has been extensively studied by generations of experimentalists and theoreticians, resulting in an extensive body of information available for critical comparisons. Both theoretical and experimental approaches to the study of matter have undergone tremendous advances in the past few decades, enabling predictions and measurements of unprecedented accuracy. Nonetheless, ten-electron diatomic molecules, such as HF, still present challenges for electronic structure methods as they are applied to an ever-expanding list of observables. The excellent agreement between theory and experiment for the large number of ground and low-lying excited-state properties of HF, which are described in the present work, reinforces the belief that at the current state of development ab initio methods provide a tool of great power and generality for the study of small molecules. For the notable exceptions where theory and experiment still differ, including notoriously difficult examples such as the second hyperpolarizability for the HF ground state and the 19F isotropic hyperfine splitting in HF+, confidence in the robustness of the theoretical methods suggests a call for renewed experimental work.