Experimental and Theoretical IR Spectra of 2-Nitrosopyridines

0552733 - ÚOCHB 2022 RIV HR eng J - Článek v odborném periodiku
Varga, Katarina - Vančik, H. - Mihalić, Z.
Experimental and Theoretical IR Spectra of 2-Nitrosopyridines.
Croatica Chemica Acta. Roč. 93, č. 4 (2020), s. 339-347. ISSN 0011-1643. E-ISSN 1334-417X
Institucionální podpora: RVO:61388963
Klíčová slova: cryogenic photolysis * 2-nitrosopyridine * nitroso monomers * vibrational spectra * double-hybrid density functionals * DSD-PBEP86-D3(BJ) * harmonic frequencies * anharmonic frequencies * scaling factors
Obor OECD: Organic chemistry
Impakt faktor: 0.887, rok: 2020
Způsob publikování: Open access
https://doi.org/10.5562/cca3820

Previously unknown IR spectra of 2-nitrosopyridines 1−3 were recorded in the solid phase after cryogenic photolysis of their dimers, and identified by the comparison with the corresponding theoretical spectra. Optimal results were obtained with double-hybrid (DH) density functionals and def2-TZVP basis set, the best being DSD-PBEP86-D3(BJ), B2GP-PLYP-D3(BJ) and mPW2-PLYP-D2. Experimental frequencies were obtained by scaling harmonic frequencies with appropriate scaling factors, either taken from the literature or calculated using modified HFREQ2014 dataset. In the case of DH functionals, anharmonic frequencies do not offer any advantage in comparison with the scaled harmonic ones. Unexpectedly, all non-DH density functionals, including highly praised ωB97X-V and ωB97M-V, have serious problems with normal modes containing N=O bond stretching vibration. It was concluded that the origin of the problem is in the nitroso group itself, most likely caused by its multireference character. The best results among non-DH functionals were achieved at TPSSh-D3(BJ)/def2-TZVP level of theory.
Trvalý link: http://hdl.handle.net/11104/0327845