The UV-Vis spectrum of the solvated purine derivative Hypoxanthine (HYX) is investigated using the Quantum Mechanics/Fluctuating Charges (QM/FQ) multiscale approach combined with a sampling of configurations through atomistic Molecular Dynamics (MD) simulations. Keto 1H7H and 1H9H tautomeric forms of HYX are the most stable in aqueous solution and form different stable complexes with the surrounding water molecules, ultimately affecting the electronic absorption spectra. The final simulated spectrum resulting from the combination of the individual spectra of tautomers agrees very well with most of the characteristics in the measured spectrum. The importance of considering the effect of the solute tautomers and, in parallel, the contribution of the different solvent arrangements around the solute when modeling spectral properties, is highlighted. In addition, the high quality of the computed spectra leads to suggesting an alternative way for acquiring tautomeric populations from combined computational/experimental spectra.

When Tautomers Matter: UV-Vis Absorption Spectra of Hypoxanthine in Aqueous Solution from Fully Atomistic Simulations

Gomez, Sara
;
Cappelli, Chiara
2024

Abstract

The UV-Vis spectrum of the solvated purine derivative Hypoxanthine (HYX) is investigated using the Quantum Mechanics/Fluctuating Charges (QM/FQ) multiscale approach combined with a sampling of configurations through atomistic Molecular Dynamics (MD) simulations. Keto 1H7H and 1H9H tautomeric forms of HYX are the most stable in aqueous solution and form different stable complexes with the surrounding water molecules, ultimately affecting the electronic absorption spectra. The final simulated spectrum resulting from the combination of the individual spectra of tautomers agrees very well with most of the characteristics in the measured spectrum. The importance of considering the effect of the solute tautomers and, in parallel, the contribution of the different solvent arrangements around the solute when modeling spectral properties, is highlighted. In addition, the high quality of the computed spectra leads to suggesting an alternative way for acquiring tautomeric populations from combined computational/experimental spectra.
2024
Settore CHIM/02 - Chimica Fisica
Hypoxanthine; MD; Quantum Mechanics/Fluctuating Charges; Tautomers; UV-Vis spectra
File in questo prodotto:
File Dimensione Formato  
hyx_wiley.pdf

embargo fino al 15/05/2025

Tipologia: Accepted version (post-print)
Licenza: Solo Lettura
Dimensione 9.2 MB
Formato Adobe PDF
9.2 MB Adobe PDF   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11384/142323
Citazioni
  • ???jsp.display-item.citation.pmc??? 0
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact