Ultraviolet absorption spectra, structure, vibrations, and theoretical calculations of 2-fluoro- and 3-fluoropyridine in their electronic excited states

Abstract

The ultraviolet absorption spectra of 2-fluoropyridine (2FPy) and 3-fluoropyridine (3FPy) vapors have been collected and assigned. For 2FPy about 150 bands were observed for the transitions to the vibronic levels of the S(pi, pi*) state at 38 030.4 cm (1). Both single quantum jump transitions to A' states and double quantum jumps transitions involving A '' modes were observed allowing most of the vibrational frequencies in the excited state to be identified. For 3FPy more than a hundred absorption bands associated with the S(n, pi*) state at 35 051.7 cm (1) and about 40 broad bands associated with the S(pi, pi*) state at 37 339 cm (1) were observed. The experimental work was complemented by ab initio calculations. (C) 2011 Elsevier B. V. All rights reserved.