19 research outputs found
Dimers of the Higher-Energy Conformer of Formic Acid: Experimental Observation
We report on the first experimental observation of formic acid dimers composed of two molecules of the higher-energy cis conformer. The cisâcis formic acid dimers are prepared in an argon matrix by selective vibrational excitation of the ground state trans conformer (deuterated form HCOOD) combined with thermal annealing of the matrix at about 30 K. Five cisâcis formic acid dimers are predicted by ab initio calculations (interaction energies from â16.9 to â27.2 kJ molËÂč), and these structures are used for the assignment of the experimental spectra. Selective vibrational excitation of the obtained cisâcis dimers leads to the formation of several transâcis dimers, which supports the proposed assignments.peerReviewe