Spin systems nomenclature

The simple one-pulse experiment is shown below, the delay dl is called the relaxation delay and it ensures that in a multi-scan experiment the spin system has returned to equilibrium before the next pulse (see Check it 5.2.1.5). The delay dlO is not normally part of the ordinary sequence scheme and represents the pre-acquisition delay (Bruker nomenclature del, de2). This delay is automatically inserted to enable time for switching between transmit and receive mode to minimize pulse breakthrough. For further aspects the reader is referred to section S.2.3.4 Check its 3.2.3.4 and 3.2.3.6). 

The remaining chapter is divided into four sections. The following two sections review briefly the theory of spin-spin coupling constant calculations, report the computational details of the calculations and describe the nomenclature used in this work. In Section 4, the results of the LDBS study are discussed. It starts with a subsection on the converged results for the model systems studied here. Finally, the last section summarizes the conclusions of the present work. 

Let us first consider our problem with neglect of the spin of the electrons, which we shall then discuss toward the end of the section. The system comprises two hydrogen nuclei, A and B, and two electrons, whose coordinates we shall designate by the symbols 1 and 2. Using the nomenclature of Figure 43-1, the wave equation for the two electrons corresponding to fixed positions of the two nuclei is... 

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