IQA data of cis-trans Proline isomerization in small peptides

We carried out quantum mechanical (QM) calculations aimed to investigate the cis-trans equilibria of short peptides: Ace-Y-Nme, Ace-X-Y-Nme, and Leu-Y with X=Gln, Leu, Tyr and Y=Pro, Ala. Using the interacting quantum atom method, we decomposed the average QM energies into physical components. The tar files deposited in this dataset contain the IQA data in csv format, including Cartesian coordinates, atomic charges, energy descriptors, etc. For each peptide model, we performed 100 QM calculations (200 for zwitterions) at the HF-D3/cc-pVTZ SMD level on structures obtained from MD simulations in explicit solvent that were previously relaxed using QM/MM calculations (HF-D3/cc-pVDZ // AMBER FF19SB; only solute molecules were allowed to move). The QM energies were then decomposed using the IQA method implemented in PROMOLDEN. IQA calculations with large numerical errors in the total reconstructed energy were discarded. Details of the IQA protocol can be found at https://doi.org/10.1002/cphc.201701021 and https://doi.org/10.1002/cphc.201800733.