Ground-State Structure of the Proton-Bound Formate Dimer by Cold-Ion Infrared Action Spectroscopy.
Angew Chem Int Ed Engl
; 57(33): 10615-10619, 2018 Aug 13.
Article
em En
| MEDLINE
| ID: mdl-29923287
ABSTRACT
The proton-bound dicarboxylate motif, RCOO- â
H+ â
- OOCR, is a prevalent chemical configuration found in many condensed-phase systems. The proton-bound formate dimer HCOO- â
H+ â
- OOCH was studied utilizing cold-ion IR action spectroscopy in the range 400-1800â
cm-1 . The spectrum obtained at ca. 0.4â
K of ions captured in He nanodroplets was compared to that measured at ca. 10â
K by photodissociation of Ar-ion complexes. Similar band patterns are obtained by the two techniques that are consistent with calculations for a C2 symmetry 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 600â
cm-1 . Multidimensional anharmonic calculations reveal that the bridging proton motion is strongly coupled to the flanking -COO- framework, an effect that is in line with the expected change in -C=O bond rehybridization upon protonation.
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Base de dados:
MEDLINE
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Alemanha