case the OAM has an extrinsic contribution , $L_z^{\rm ext}=-P_x Y_{\ell}^{\sigma}$ (\[eqn:14\]): $$\label{eqn:47}
L_z^{\rm ext}=\gamma^2 L_z,~L_z^{\rm int}=(1-\gamma^2) L_z.$$ Hence, the Hall effects of light can be interpreted as an *intrinsic-to-extrinsic OAM conversion* [@SHE1; @OHE1] which is also accompanied by generation of a transverse OAM component $L_x^{\rm ext}=P_z Y_{\ell}^{\sigma}=- \gamma\cot\theta_0 L_z$ [@Aiello]. The total conversion is achieved at $\delta\rightarrow 0$, $\gamma\rightarrow 1$.

Conclusion
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To summarize, we have revisited the problem of the identification of the spin and orbital angular momenta of nonparaxial light in free space. It has been shown that this issue is closely related to the determination of the position of the center of gravity of a light beam or a wave packet. We have given an exact self-consistent solution to these problems in terms of quantum-operator formalism and using classical Poynting energy flows. In the helicity representation, taking into account the transverse nature of the electromagnetic fields, the operators of the OAM, SAM, and position become diagonal, but exhibit non-canonical commutation relations. We have shown that the unusual features of these operators originate from the Berry-phase terms and can be associated with manifestations of the spin-orbit interaction of light. Indeed, anomalous Berry terms in the OAM and 