Dynamics of protonated oxalate from machine-learned simulations and experiment: infrared signatures, proton transfer dynamics and tunneling splittings.

ABSTRACT: The infrared spectroscopy and proton transfer dynamics together with the associated tunneling splittings for H/D-transfer in oxalate are investigated using a machine learning-based potential energy surface (PES) of CCSD(T) quality, calibrated against the results of new spectroscopic measurements. Second order vibrational perturbation calculations (VPT2) very successfully describe both the framework and H-transfer modes compared with the experiments. In particular, a newly observed low-intensity signature at 1666 cm^-1 was correctly predicted from the VPT2 calculations. An unstructured band centered at 2940 cm^-1 superimposed on a broad background extending from 2600 to 3200 cm^-1 is assigned to the H-transfer motion. The broad background involves a multitude o

SUBMITTER: Andreichev V 

PROVIDER: S-EPMC12538276 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature