Photo-Induced Tautomerism of Isocytosine in Aqueous Solution when Irradiated with UVC Light
It was found that the irradiation of aqueous solution of isocytosine with UVC light provokes an oxo-hydroxy phototautomerism of the compound with a rate constant of 5.29× 10-3 min-1. It was observed a backward reaction, after removing the UV light source, with a rate constant of 0.12×10-3 min-1. Two...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Turkish Chemical Society
2024-02-01
|
| Series: | Journal of the Turkish Chemical Society, Section A: Chemistry |
| Subjects: | |
| Online Access: | https://dergipark.org.tr/tr/download/article-file/3255867 |
| _version_ | 1797215221036613632 |
|---|---|
| author | Mina Todorova Tsvetina Cherneva Rumyana Bakalska Vassil Delchev |
| author_facet | Mina Todorova Tsvetina Cherneva Rumyana Bakalska Vassil Delchev |
| author_sort | Mina Todorova |
| collection | DOAJ |
| description | It was found that the irradiation of aqueous solution of isocytosine with UVC light provokes an oxo-hydroxy phototautomerism of the compound with a rate constant of 5.29× 10-3 min-1. It was observed a backward reaction, after removing the UV light source, with a rate constant of 0.12×10-3 min-1. Two mechanisms of the phototautomerism were investigated at the B3LYP/aug-cc-pVDZ theoretical level in water surroundings (PCM). The first one showed a consecutive dissociation and association of a proton through conical intersections S0/S1 whose structures were located at the same theoretical level in the gas phase. It occurs along the 1πσ* excited-state reaction pathway. The more probable mechanism includes an excited-state H-transfer supported by a water molecule as a catalyst. It occurs along the 1ππ* excited-state reaction pathway which we found over the IRC ground-state energy curve. The water molecule drastically reduces the energy barrier in the ground state as well in the excited state. |
| first_indexed | 2024-04-24T11:26:37Z |
| format | Article |
| id | doaj.art-4e6cc5cce4484b169e81d1ef97dcccf2 |
| institution | Directory Open Access Journal |
| issn | 2149-0120 |
| language | English |
| last_indexed | 2024-04-24T11:26:37Z |
| publishDate | 2024-02-01 |
| publisher | Turkish Chemical Society |
| record_format | Article |
| series | Journal of the Turkish Chemical Society, Section A: Chemistry |
| spelling | doaj.art-4e6cc5cce4484b169e81d1ef97dcccf22024-04-10T16:03:42ZengTurkish Chemical SocietyJournal of the Turkish Chemical Society, Section A: Chemistry2149-01202024-02-0111132133010.18596/jotcsa.1325480182Photo-Induced Tautomerism of Isocytosine in Aqueous Solution when Irradiated with UVC LightMina Todorova0Tsvetina Cherneva1Rumyana Bakalska2Vassil Delchev3University of PlovdivUniversity of PlovdivUniversity of PlovdivUniversity of PlovdivIt was found that the irradiation of aqueous solution of isocytosine with UVC light provokes an oxo-hydroxy phototautomerism of the compound with a rate constant of 5.29× 10-3 min-1. It was observed a backward reaction, after removing the UV light source, with a rate constant of 0.12×10-3 min-1. Two mechanisms of the phototautomerism were investigated at the B3LYP/aug-cc-pVDZ theoretical level in water surroundings (PCM). The first one showed a consecutive dissociation and association of a proton through conical intersections S0/S1 whose structures were located at the same theoretical level in the gas phase. It occurs along the 1πσ* excited-state reaction pathway. The more probable mechanism includes an excited-state H-transfer supported by a water molecule as a catalyst. It occurs along the 1ππ* excited-state reaction pathway which we found over the IRC ground-state energy curve. The water molecule drastically reduces the energy barrier in the ground state as well in the excited state.https://dergipark.org.tr/tr/download/article-file/3255867conical intersections s0/s1excited statesisocytosinetd/dft methodsuv irradiation |
| spellingShingle | Mina Todorova Tsvetina Cherneva Rumyana Bakalska Vassil Delchev Photo-Induced Tautomerism of Isocytosine in Aqueous Solution when Irradiated with UVC Light Journal of the Turkish Chemical Society, Section A: Chemistry conical intersections s0/s1 excited states isocytosine td/dft methods uv irradiation |
| title | Photo-Induced Tautomerism of Isocytosine in Aqueous Solution when Irradiated with UVC Light |
| title_full | Photo-Induced Tautomerism of Isocytosine in Aqueous Solution when Irradiated with UVC Light |
| title_fullStr | Photo-Induced Tautomerism of Isocytosine in Aqueous Solution when Irradiated with UVC Light |
| title_full_unstemmed | Photo-Induced Tautomerism of Isocytosine in Aqueous Solution when Irradiated with UVC Light |
| title_short | Photo-Induced Tautomerism of Isocytosine in Aqueous Solution when Irradiated with UVC Light |
| title_sort | photo induced tautomerism of isocytosine in aqueous solution when irradiated with uvc light |
| topic | conical intersections s0/s1 excited states isocytosine td/dft methods uv irradiation |
| url | https://dergipark.org.tr/tr/download/article-file/3255867 |
| work_keys_str_mv | AT minatodorova photoinducedtautomerismofisocytosineinaqueoussolutionwhenirradiatedwithuvclight AT tsvetinacherneva photoinducedtautomerismofisocytosineinaqueoussolutionwhenirradiatedwithuvclight AT rumyanabakalska photoinducedtautomerismofisocytosineinaqueoussolutionwhenirradiatedwithuvclight AT vassildelchev photoinducedtautomerismofisocytosineinaqueoussolutionwhenirradiatedwithuvclight |