A Polar Isomer of Formic Acid Dimer Formed in Helium Nanodroplets
1.
SYSNO ASEP
0101109
Document Type
J - Journal Article
R&D Document Type
Journal Article
Subsidiary J
Ostatní články
Title
A Polar Isomer of Formic Acid Dimer Formed in Helium Nanodroplets
Title
Polární isomer dimerů kyseliny mravenčí vytvořený v nano-kapičkách helia
Author(s)
Madeja, F. (DE) Havenith, M. (DE) Nauta, K. (US) Miller, R. E. (US) Chocholoušová, Jana (UFCH-W) Hobza, Pavel (UFCH-W)
Source Title
Journal of Chemical Physics. - : AIP Publishing
- ISSN 0021-9606
Roč. 120, č. 22 (2004), s. 10554-10560
Number of pages
7 s.
Language
eng - English
Country
US - United States
Keywords
resolution infrared-spectroscopy ; double-resonance spectroscopy ; ab initio calculations
Subject RIV
CF - Physical ; Theoretical Chemistry
R&D Projects
LN00A032 GA MŠMT - Ministry of Education, Youth and Sports (MEYS)
CEZ
AV0Z4040901 - UFCH-W
Annotation
The infrared spectrum of formic acid dimers in helium nanodroplets has been observed corresponding to excitation of the "free" OH and CH stretches. The experimental results are consistent with a polar acyclic structure for the dimer. The formation of this structure in helium, as opposed to the much more stable cyclic isomer with two O-H.O hydrogen bonds, is attributed to the unique growth conditions that exist in helium droplets, at a temperature of 0.37 K. Theoretical calculations are also reported to aid in the interpretation of the experimental results. At long range the intermolecular interaction between the two monomers is dominated by the dipole-dipole interaction, which favors the formation of a polar dimer. By following the minimum-energy path, the calculations predict the formation of an acyclic dimer having one O-H.O and one C-H.O contact. This structure corresponds to a local minimum on the potential energy surface and differs significantly from the structure observed.
