Paramagnetic spin orbit

The equivalent of the spin-other-orbit operator in eq. (8.30) splits into two contributions, one involving the interaction of the electron spin with the magnetic field generated by the movement of the nuclei, and one describing the interaction of the nuclear spin with the magnetic field generated by the movement of the electrons. Only the latter survives in the Born-Oppenheimer approximation, and is normally called the Paramagnetic Spin-Orbit (PSO) operator. The operator is the one-electron part of... 

According to NMR theory [30], contributions to spin-spin coupling come from paramagnetic spin-orbital (PSO), diamagnetic spin-orbital (DSO), Fermi contact (FC), and spin-dipolar (SD) interactions [30] ... 

From the three operators obtained by differentiating the Hamiltonian with respect to the nuclear magnetic moments (Equation (2.12)) only the singlet paramagnetic spin-orbital (PSO) operator... 

Paramagnetic Spin-Orbit (PSO) operator. The operator is the one-electron part of which in its time-independent form (setting A = 0 in eq. (8.81) can be written as ... 

The nonrelativistic limit of this operator yields the paramagnetic spin-orbit (PSO) contribution of Ramsey s theory. The remaining terms in eq. (4.10b) result in the ZORA relativistic spin-orbit Hamiltonian,... 

As mentioned above there are four main contributions to the nuclear spin-spin coupling constants the Fermi contact (FC), the paramagnetic spin-orbit (PSO), the spin-dipolar (SD) and the diamagnetic spin-orbit (DSO) contributions. The Fermi contact term is usually the most important of these and also the most sensitive to geometry changes [8]. The Fermi contact contribution arises from the interactions between the terms containing S(riM) and < (riN) in the operators Hon for nuclei N and M (see Eqn. (12)). 

The singlet paramagnetic spin-orbit (PSO) operator the triplet Fermi contact (FC) operator... 

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