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International Journal Of Chemistry, Mathematics And Physics(IJCMP)

Potential energy curves, spectroscopic parameters, vibrational levels and molecular constants for 37 low-lying electronic states of He2

Michel Douglas Epée Epée , Roland Kevin Douthio Mbayang


International Journal of Chemistry, Mathematics And Physics(IJCMP), Vol-9,Issue-2, April - June 2025, Pages 24-37 , 10.22161/ijcmp.9.2.4

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Article Info: Received: 20 May 2025; Received in revised form: 18 Jun 2025; Accepted: 22 Jun 2025; Available online: 26 Jun 2025

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A manifold of singlet and triplet electronic states of He2 is characterized theoretically using the R-matrix method. Potential energy curves have been calculated for (_^"1" )_"u" ^"+" , (_^"1" )_"g" ^"+" , (_^"1" )_"u" , (_^"1" )_"g" , (_^"3" )_"u" ^"+" , (_^"3" )_"g" ^"+" , (_^"3" )_"u" , (_^"3" )_"g" electronic states. These potential curves are then fitted to analytical potential energy functions (APEFs) using the Murrell-Sorbie potential function. The spectroscopic parameters, such as D_e, ω_e, ω_e x_e , B_e, α_e are determined using the obtained APEFs, and compared with theoretical and experimental data available. A whole set of vibrational level G(v) and inertial rotation constant B_v predicted for these electronic states by solving the ro-vibrational Schrödinger equation of nuclear motion using Numerov’s method completes these characterization.

Spectroscopic parameters, molecular constant, vibrational level.

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