The influence of chalcogen atom on conformation and phase transition in chalcogenazinoquinolinium monoiodides

Crystalline chalcogenazinoquinolinium monoiodides, where the chalcogen atom is oxygen and sulfur, have been studied using a combination of X-ray diffraction, Raman and UV-vis spectroscopies and photoluminescence experimental techniques. Periodic quantum-chemical calculations have been performed to characterize the features of electronic structure and vibrational assignment. X-ray diffraction and Raman spectroscopy experiments consistently reveal phase transition of thiazinoquinolinium monoiodide at low temperatures with the decrease of symmetry to P1. The luminescence study for oxazinoquinolinium monoiodide reveals the excitation maximum at 532   nm and emission at 650   nm with significantly higher intensity than for the thiazinoquinolinium derivative. The studied chalcogenazinoquinolinium monoiodides demonstrate high values of Stokes shift up to 150   nm.

Source: Acta Crystallographica Section B - July 14, 2021 Category: Chemistry Authors: Yushina, I. Krylov, A. Leonidov, I.I Batalov, V. Chen, Y.-S. Wang, S.G. Stash, A. Bartashevich, E. Tags: organic monoiodide phase transition Raman spectroscopy luminescence halogen bond research papers Source Type: research