Ab initio/GIAO-MP2-calculated structures and (11)B-(13)C NMR chemical shift relationship in hypercoordinate onium-carbonium dications and isoelectronic onium-boronium cations.
نویسندگان
چکیده
The boronium-carbonium ion continuum was extended to include hypercoordinated onium-carbonium dications and the isoelectronic onium-boronium cation analogs. Structures and (13)C and (11)B NMR chemical shifts of the onium-carbonium dications and the corresponding isoelectronic and isostructural onium-boronium cations were calculated with the ab initio/GIAO-MP2 method. The data show a good linear correlation between (11)B and (13)C NMR chemical shifts, indicating that the same factors that determine the chemical shifts of the boron nuclei also govern the chemical shifts of carbon nuclei of these hypercoordinated onium ions and dications.
منابع مشابه
Structures and stabilities of higher coordinate onium-boronium dications (X(+)BH(3)+ and X(+)BH(5)+; X = NH(3), PH(3), H(2)O, and H(2)S).
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ورودعنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 99 15 شماره
صفحات -
تاریخ انتشار 2002