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Title: Ground‐State Structure of the Proton‐Bound Formate Dimer by Cold‐Ion Infrared Action Spectroscopy
Abstract

The proton‐bound dicarboxylate motif, RCOO⋅H+OOCR, is a prevalent chemical configuration found in many condensed‐phase systems. The proton‐bound formate dimer HCOO⋅H+OOCH was studied utilizing cold‐ion IR action spectroscopy in the range 400–1800 cm−1. The spectrum obtained at ca. 0.4 K of ions captured in He nanodroplets was compared to that measured at ca. 10 K by photodissociation of Ar‐ion complexes. Similar band patterns are obtained by the two techniques that are consistent with calculations for a C2symmetry structure with a proton shared equally between the two formate moieties. Isotopic substitution experiments point to the nominal parallel stretch of the bridging proton appearing as a sharp, dominant feature near 600 cm−1. Multidimensional anharmonic calculations reveal that the bridging proton motion is strongly coupled to the flanking −COOframework, an effect that is in line with the expected change in −C=O bond rehybridization upon protonation.

 
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NSF-PAR ID:
10064067
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
130
Issue:
33
ISSN:
0044-8249
Page Range / eLocation ID:
p. 10775-10779
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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