Implementation of the IPPP–CLOPPA–INDO/S method for the study of indirect nuclear spin coupling constants and its application to molecules containing tin nuclei

• Autores: Botek, Edith L.; Aucar, Gustavo Adolfo; Cory, Marshall G.; Zerner, Michael C.
• Año de publicación: 2000
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Indo/S; Tin; Indirect Nuclear Spin Coupling Constants; Ippp–Cloppa–Indo/S; Atomic Parameters; Relativistic Effects
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

The inner projection of the polarization propagator, using contributions from localized orbitals, IPPP–CLOPPA, and using the intermediate neglect of the differential overlap model parameterized for spectroscopy, INDO/S, was implemented and used to calculate indirect nuclear spin coupling constants. The resulting model was tested on a group of small- and medium-size model compounds by comparing its performance with that of other semi-empirical methods and experiments where available. It is shown that in general the INDO/S approximation with the use of S N 2 (0) and r N −3 atomic parameters taken from the INDO and AM1 approaches is the most suitable scheme to describe coupling constants. The introduction of atomic parameters for S N 2 (0) and r N −3 in the case of heavy nuclei like Sn, is a critical step. The correction of the bonding beta parameter for this nucleus was also necessary within the INDO/S approximation to improve the accuracy and to better account for indirect relativistic effects. The application of this parameterization was accomplished in a series of tetrastannacyclohexanes and different pathways for coupling transmission were analyzed.
Fil: Botek, Edith L.. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas Naturales y Agrimensura; Argentina
Fil: Aucar, Gustavo Adolfo. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas Naturales y Agrimensura; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Fil: Cory, Marshall G.. University of Florida; Estados Unidos
Fil: Zerner, Michael C.. University of Florida; Estados Unidos