Transfer learned potential energy surfaces: accurate anharmonic vibrational dynamics and dissociation energies for the formic acid monomer and dimer.

ABSTRACT: The vibrational dynamics of the formic acid monomer (FAM) and dimer (FAD) is investigated from machine-learned potential energy surfaces at the MP2 (PES_MP2) and transfer-learned (PES_TL) to the CCSD(T) levels of theory. The normal mode (MAEs of 17.6 and 25.1 cm^-1) and second order vibrational perturbation theory (VPT2, MAEs of 6.7 and 17.1 cm^-1) frequencies from PES_TL for all modes below 2000 cm^-1 for FAM and FAD agree favourably with experiment. For the OH stretch mode the experimental frequencies are overestimated by more than 150 cm^-1 for both FAM and FAD from normal mode calculations. Conversely, VPT2 calculations on PES_TL for FAM reproduce the experimental OH frequency to within 22 cm^-1.

SUBMITTER: Kaser S 

PROVIDER: S-EPMC8890265 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature