PHYS 593 |
| The stability of hydrated gas-phase cluster ions is determined by the balance between various competing electrostatic and hydrogen bonding interactions. In K+(Tryptamine) cluster ions, a favorable electrostatic interaction between the potassium cation and the tryptamine NH2 lone pair stabilizes the high-energy Gph(in) and Gpy(in) conformers of neutral tryptamine. Previous studies of Tryptamine(H2O)n clusters indicate that the hydrating water molecules favor stabilizing the neutral minimum energy Gpy(out) tryptamine conformer. In this scheme, the first water molecule interacts directly with the NH2 lone pair and is located to the side of the tryptamine monomer. By incorporating a potassium cation, however, the minimum energy tryptamine-water configuration is disrupted in order to maximize the electrostatic interactions with the cation, shifting so that the tryptamine-water interaction includes a π-hydrogen bond between the water and the phenyl ring of tryptamine.
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PHYS Poster Session - Computational Spectroscopy and Reaction Dynamics
7:30 PM-10:00 PM, Wednesday, April 9, 2008 Morial Convention Center -- Hall A, Poster
Sci-Mix
Division of Physical Chemistry |
