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Title: Unravelling the structures of sodiated β-cyclodextrin and its fragments
We present cryogenic infrared spectra of sodiated β-cyclodextrin [β-CD + Na] + , a common cyclic oligosaccharide, and its main dissociation products upon collision-induced dissociation (CID). We characterize the parent ions using high-resolution ion mobility spectrometry and cryogenic infrared action spectroscopy, while the fragments are characterized by their mass and cryogenic infrared spectra. We observe sodium-cationized fragments that differ in mass by 162 u, corresponding to B n /Z m ions. For the m / z 347 product ion, electronic structure calculations are consistent with formation of the lowest energy 2-ketone B 2 ion structure. For the m / z 509 product ion, both the calculated 2-ketone B 3 and the Z 3 structures show similarities with the experimental spectrum. The theoretical structure most consistent with the spectrum of the m / z 671 ions is a slightly higher energy 2-ketone B 4 structure. Overall, the data suggest a consistent formation mechanism for all the observed fragments.  more » « less
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Journal Name:
Physical Chemistry Chemical Physics
Page Range / eLocation ID:
13714 to 13723
Medium: X
Sponsoring Org:
National Science Foundation
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