IMIT   21220
INSTITUTO DE MODELADO E INNOVACION TECNOLOGICA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
A full relativistic formalism that gives new insight into magnetic molecular properties
Autor/es:
GUSTAVO A. AUCAR, ALEJANDRO F. MALDONADO Y CARLOS A. GIMENEZ
Lugar:
Santiago de Compostela
Reunión:
Conferencia; 9th triennial Congress of the World Association of Theoretical and Computational Chemist WATOC; 2011
Institución organizadora:
WATOC
Resumen:
Recent developments of full
relativistic formalisms and its implementation in computational codes gives now
the opportunity to calculate and analyse the electronic origin of magnetic
molecular properties of heavy-atom containing molecules, and improve our
understanding of such properties.
When four-component methods are
applied for studying the electronic behaviour of molecular systems new physical
insights do arise naturally. In fact new mechanisms and new phenomena should be
expected. Dirac-like operators replace its non relativistic counterparts and so
what we are used to treat within NR quantum chemistry are not any longer what
they were.
In this talk we will show new physical
insight that makes more beautiful the understanding of NMR spectroscopic
parameters when worked out within the full relativistic formalism from the
outset. It will be based on polarization propagators, which are powerful
theoretical tools as all propagator methods are. We will focus on the origin of
diamagnetic contributions (virtual creation and annihilation of electron-positron
pairs), spin and time reversal symmetry, gauge dependence and covariance; and the
analysis of results of calculations of both spectroscopic parameters when the
finite size of nuclei is considered and their values for molecules which
contain more than three heavy atoms, like SnBrnI4-n.