Magnetic Resonance Spectroscopy: Singlet and Doublet Electronic States

The aim of this chapter has been to provide an overview of current computational approaches in some specific areas of Magnetic Resonance Spectroscopy. Apart from theoretical considerations, the focus on singlet and doublet electronic states reflects the fact that in these specific fields computational spectroscopy has nowadays reached the stage of a mature technique. Thus, for example, comparisons between measured and computed values of chemical shifts are becoming an important tool for experimental studies in structural organic chemistry; likewise, hyperfine coupling constant are routinely calculated to gain insight into the behavior of spin-probes. Even more demanding computational applications, e.g. those involving the estimation of spin-spin coupling constants, are on their way to enter into routine use even by non specialists. In this spirit, the theoretical presentation has been kept at a reasonably accessible level, and a number “case studies” have been provided in order to illustrate the potentiality of the techniques introduced: this plan should contribute to further promote the introduction of computational approaches within standard experimental studies, which, in this as in many other fields of research, allows for enhanced understanding of phenomena, faster and more efficient characterization protocols, and innovative chemical results.