Theoretical Study on the Structure and Electronic Excited States of the FNO Molecule

We utilize the internally contracted explicitly correlated multireference configuration interaction (icMRCI-F12) method, incorporating the Davidson correction, to perform comprehensive <i>ab initio</i> studies on the FNO molecule. The vertical transition energies and the oscillator strength are calculated for 14 electronic states of FNO. For the first time, the potential energy curves of these states are examined along the F-N-O bond angle, N-O, and N-F bond distances, respectively. On the basis of these computational results, we discuss the dissociation mechanism of the FNO molecule in the ultraviolet region. Our findings will provide valuable insights into the electronic state behavior and photodissociation of halogenated nitrenes.