Maciej J. Nowak

TL;DR: In this paper, the results of ab initio calculations of infrared (IR) spectra of 4-hydroxypyrimidine and 4(3H)-pyrimidinone are reported.

TL;DR: In this paper, the authors compared the IR spectrum of tropolone (2-hydroxy-2,4,6-cycloheptatriene-1-one) isolated in Ar and N2 matrices with the spectra theoretically calculated at the DFT (density functional theory) levels.

TL;DR: Theoretical ab initio calculations are performed to provide support for the hypothesis that the gas phase ratio of 2-hydroxypyridine/2(1 H )-pyridinone tautomers results from the thermodynamic equilibrium which exists between cyclic hydrogen-bonded oxo-oxo and hydroxy-hydroxy dimers as discussed by the authors.

TL;DR: In this paper, the inversion vibration was treated as being uncoupled from all other nuclear degrees of freedom, and the electronic energy was calculated at the second-order Mo/ller-ller-Plesset perturbation theory level at selected values of ω to form a doublewell curve describing a model potential within which the nuclei move during the vibration.

TL;DR: Good agreement between the experimental spectra and the spectra calculated for thiol N9H tautomer supported the identification of the dominant tautomers and allowed for the reliable assignment of the bands observed in the experimental IR spectrum.