Repozytorium publikacji - Politechnika Gdańska

This is the first comprehensive investigation on the anionic species formed in collisions of fast neutral potassium (K) atoms with neutral hexachlorobenzene (C6Cl6) molecules in the laboratory frame range from 10 up to 100 eV. In such ion-pair formation experiments, we also report a novel K+ energy loss spectrum obtained in the forward scattering giving evidence of the most accessible electronic states. The vertical electron affinity of (–3.76 ± 0.20) eV has been obtained and assigned to a purely repulsive transition from C6Cl6 ground state to a σCCl*state of the temporary negative ion yielding Cl– formation. These experimental findings have also been supported by state-of-the art theoretical calculations on the electronic structure of C6Cl6 in the presence of a potassium atom and used to help analyse the lowest unoccupied molecular orbitals participating in the collision process. From the time-of-flight mass spectra recorded in the wide collision energy range, more than 80% of the total anion yield is due to the undissociated parent anion C6Cl6 –, C6Cl5 – and Cl– formation. Other fragment anions that require complex internal reactions within the temporary negative ion formed after electron transfer, and accounting for less than 20% of the total yield, have been assigned to C6Cl4–, C3Cl2–, C2Cl– and Cl2–. The joint experimental and theoretical methodologies employed in these electron transfer studies, are the most comprehensive and unique assignments of the hexachlorobenzene anionic species and the role of C6Cl6 electronic states in collision induced dissociation to date.

Autorzy

• Sarvesh Kumar,
• mgr inż. Tymon Kilich link otwiera się w nowej karcie ,
• dr hab. inż. Marta Łabuda link otwiera się w nowej karcie ,
• Gustavo García,
• Paulo Limão-Vieira