Selective excitation of single lines of a multiplet for interpretation of spectra of complex multicomponent systems

Abstract

The article discusses the most important aspects of the selective RF excitation of multiplet single lines, an approach that makes it possible to simplify the spectra of complex multicomponent systems, to measure the spin–spin coupling constant, and to determine molecular structure. Semi-selective and selective methods of recording spectra are considered and theoretically substantiated based on the product operator formalism. The results are verified using quantum-mechanical calculations within the framework of the density matrix formalism. The paper demonstrates that the proposed new method leads to a significant simplification of two-dimensional nuclear magnetic resonance spectra. This makes it possible to study chemical processes and spin state exchange by observing the dynamic behavior of the multiplet structure of bound nuclei.