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Title: Isomer-specific cryogenic ion vibrational spectroscopy of the D 2 tagged Cs + (HNO 3 )(H 2 O) n=0–2 complexes: ion-driven enhancement of the acidic H-bond to water
We report how the binary HNO 3 (H 2 O) interaction is modified upon complexation with a nearby Cs + ion. Isomer-selective IR photodissociation spectra of the D 2 -tagged, ternary Cs + (HNO 3 )H 2 O cation confirms that two structural isomers are generated in the cryogenic ion source. In one of these, both HNO 3 and H 2 O are directly coordinated to the ion, while in the other, the water molecule is attached to the OH group of the acid, which in turn binds to Cs + with its –NO 2 group. The acidic OH stretching fundamental in the latter isomer displays a ∼300 cm −1 red-shift relative to that in the neutral H-bonded van der Waals complex, HNO 3 (H 2 O). This behavior is analyzed with the aid of electronic structure calculations and discussed in the context of the increased effective acidity of HNO 3 in the presence of the cation.  more » « less
Award ID(s):
1801971
PAR ID:
10150059
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Physical Chemistry Chemical Physics
Volume:
22
Issue:
8
ISSN:
1463-9076
Page Range / eLocation ID:
4501 to 4507
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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