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Title: Ab initio molecular dynamics study of sodium NMR chemical shifts in the methylamine solution of [Na + [2.2.2]cryptand Na ]
The sodium anion (Na − ) was once thought to behave like a ‘genuine’ anion, with both the [Ne] core and the 3s valence shell interacting very weakly with their environments. In the present work, following a recent study of the surprisingly small quadrupolar line widths of Na − , NMR shielding calculations were carried out for the Na − /Na + [2.2.2]cryptand system solvated in methylamine, based on ab initio molecular dynamics simulations, followed by detailed analyses of the shielding constants. The results confirm that Na − does not act like a quasi-free ion that interacts only weakly with its surroundings. Rather, the filled 3s shell of Na − interacts strongly with its chemical environment, but only weakly with the ion's own core and the nucleus, and it isolates the core from the chemical environment. As a consequence, the Na − ion appears in NMR experiments like a free ion.
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Physical Chemistry Chemical Physics
Page Range or eLocation-ID:
339 to 346
Sponsoring Org:
National Science Foundation
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