6533b7dafe1ef96bd126d958

RESEARCH PRODUCT

Matrix Isolation and Ab Initio Study of Trans−Trans and Trans−Cis Dimers of Formic Acid

Leonid KhriachtchevMarkku RäsänenA.v. DomanskayaJan LundellKseniya Marushkevich

subject

Models MolecularFormatesSpectrophotometry InfraredFormic acidDimerMolecular ConformationAb initio010402 general chemistryPhotochemistry01 natural scienceschemistry.chemical_compoundAb initio quantum chemistry methods0103 physical sciencesPhysical and Theoretical ChemistryConformational isomerism010304 chemical physicsHydrogen bondMatrix isolationStereoisomerism0104 chemical sciences3. Good healthCrystallographychemistryQuantum TheoryThermodynamicsDimerizationCis–trans isomerism

description

Six trans-trans and five trans-cis dimeric structures of formic acid (HCOOH) are revealed by ab initio calculations. Four trans-trans and two trans-cis dimers are identified in the IR absorption spectra in argon matrices. The trans-cis dimers are obtained by narrow-band IR excitation of the vibrational transitions of the trans-trans dimers. Two trans-trans (tt3 and tt6) and one trans-cis (tc4) dimer are characterized experimentally for the first time. The tunneling decay rates of two trans-cis dimers (tc1 and tc4) are evaluated at different temperatures. A greater lifetime of the trans-cis dimers at elevated temperatures compared to the cis-monomer suggests that the high-energy conformers can be stabilized upon hydrogen bonding.

yearjournalcountryeditionlanguage
2010-02-18The Journal of Physical Chemistry A
https://doi.org/10.1021/jp911515f