https://doi.org/10.1140/epjd/e2012-30495-3
Regular Article
A comparative spectroscopic study of the excited electronic states of potassium-neon and potassium-helium systems
Department of Chemistry, Birla Institute of
Technology and Science (BITS), Pilani – K.K. Birla Goa Campus, Goa
403 726,
India
a e-mail: anjanchattopadhyay@yahoo.com
Received:
8
August
2012
Received in final form:
9
October
2012
Published online:
27
December
2012
Configuration interaction studies have revealed the unexplored excited – state properties of potassium-neon and potassium-helium systems. In contrast to KHe, no potential barrier has been found in the lowest excited spin-orbit (12Π1/2) state of KNe. However, a small barrier of height 2 cm-1 and width 1.9 Åhave been predicted for the 12Πu,1/2state of the triatomic Ne-K-Ne system. Both spin-orbit components (12Π1/2, 3/2) of the diatomic and triatomic systems of potassium-neon are characterized by low binding energy values. Radiative lifetimes of these states are almost 10 ns lower than that of potassium-helium systems. Their high-lying excited states are having better binding energy values, especially, that of the triatomic ones, while huge barriers are only noticed in the high-energy 2Σ+ states. Stable exciplexes can be expected to form with respect to the two energetically similar excited states of 2Δ and 2Π symmetries. They are having radiative lifetimes of 25 ns and involved in important transitions to the 12Π state. This may eventually lead to the12Π -X2Σ+ emission near 13 330 cm-1 for KNe (12 900 cm-1 for Ne-K-Ne), which is on the lower wavelength side in comparison to potassium-helium systems. Their low-lying repulsive excited states can trigger the pumping of the blue-side and the red-side of the ns2S1/2 → np2P3/2 transition, and this may ultimately give rise to the np2P1/2 → ns2S1/2 lasing transition.
Key words: Molecular Physics and Chemical Physics
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag 2012