relation: http://publicatio.bibl.u-szeged.hu/31853/
title: Protonation of serine: conformers, proton affinities and gas-phase basicities at the "gold standard" and beyond
creator:  Nacsa András Bence
creator:  Kigyosi Mate
creator:  Czakó Gábor
subject: 01.04. Kémiai tudományok
description: The potential energy surfaces (PESs) of serine and its protonated counterparts are investigated to determine the structures of the minima. A total of 95 neutral serine, 15 N-(amino-) and 46 O-(carbonyl-)protonated serine conformers are found. Their relative energies, geometries and harmonic vibrational frequencies are determined at the MP2/aug-cc-pVDZ level of theory. To obtain highly accurate thermodynamic values, further computations are performed: the ten conformers with the lowest relative energies from each molecule type (neutral, N- and O-protonated) are further optimized using the explicitly correlated CCSD(T)-F12a/cc-pVDZ-F12 method (for neutral serine, harmonic vibrational frequencies were also computed). In addition, auxiliary corrections were determined: basis-set effects up to CCSD(T)-F12b/cc-pVQZ-F12, electron correlation effects up to CCSDT(Q), core correlation and second-order Douglas-Kroll relativistic effects along with zero-point energy contributions. Two important thermodynamic parameters (at 298.15 K), proton affinity (PA)/gas-phase basicity (GB) are calculated considering the two different protonation sites: 218.05 +/- 0.2/209.86 +/- 0.6 kcal mol(-1) and 205.87 +/- 0.2/196.36 +/- 0.3 kcal mol(-1) for the amino and carbonyl sites, respectively. The uncertainty of the determined values was approximated based on various sources including auxiliary corrections, basis-set effects, harmonic vibrational frequencies.
date: 2023
type: Folyóiratcikk
type: PeerReviewed
format: text
identifier: http://publicatio.bibl.u-szeged.hu/31853/1/PCCP_25_8891_2023.pdf
identifier:     Nacsa András Bence;  Kigyosi Mate;  Czakó Gábor: Protonation of serine: conformers, proton affinities and gas-phase basicities at the "gold standard" and beyond.   PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 25 (12).  pp. 8891-8902.  ISSN 1463-9076 (2023)     
identifier: doi:10.1039/d3cp00612c
relation: https://doi.org/10.1039/d3cp00612c
relation: 33732667
language: eng
relation: info:eu-repo/semantics/altIdentifier/doi/10.1039/d3cp00612c
rights: info:eu-repo/semantics/openAccess