Formal relations connecting different appraoches to calculate relativistic effects on molecular magnetic properties.

D. G. ZACCARI, M. C. RUIZ DE AZÚA, J. I. MELO Y C. G. GIRIBET

JOURNAL OF CHEMICAL PHYSICS

American Institute of Physics

Lugar: New York; Año: 2005 vol. 124

0021-9606

In the present work a set of formal relations connecting different approaches to calculate relativistic effects on magnetic molecular properties are proven. The linear reaponse (LR) within the elimination of the small component (ESC), Breit Pauli, and minimal-coupling approaches are compared. To this end, the leading order ESC reduction of operators within the minimal-coupling four-component approach is carried out. The equivalence of all three appraoches within the ESC approaximation is proven. It is numerically verified for the NMR nuclear-magnetic shielding tensor taking HX and CH3X (X=Br, I) as model compounds. Formal relations proving the gauge origin invariance of the full relativistic effect on the NMR nuclear-magnetic shielding tensor within the LR-ESC approach are presented.