TITLE:
Calculation of the Resonance Energies, Quantum Defect and Effective Nuclear Charge of Highly Excited Rydberg Series in the Photoionization Spectra of Se II and Rb II Ions Using the Modified Atomic Orbital Theory
AUTHORS:
Abdou Faye, Malick Sow, Moustapha Kebe, Papa Mamadou Ndiaye, Oumar Baba Dia, Cheikh Ndiaye, Cheikh Tidjane Diouf, Astou Ngom, Oumar Absatou Niasse
KEYWORDS:
Rydberg Series, Resonance Energy, Quantum Defect, Photoionization, Effective Charge and Modified Atomic Orbital Theory
JOURNAL NAME:
Journal of Applied Mathematics and Physics,
Vol.14 No.6,
June
22,
2026
ABSTRACT: In this paper, we reported the energy positions, quantum defect and effective nuclear charge of the
4
s
2
4
p
2
(
3
P
2
)nd
,
4
s
2
4
p
2
(
1
D
2
)ns
,
4
s
2
4
p
2
(
2
D
2
)ns(
2
D
2
)
,
4
s
2
4
p
2
(
1
D
2
)nd(
2
P
1/2
o
)
and
4
s
2
4
p
2
(
2
D
2
)ns(
2
S
)
Rydberg series of Se+ ions and
4
s
2
4
p
2
(
2
P
1/2
o
)nd(
1
P
1
o
)
Rydberg series of Rb+. Calculations are performed using the semi-empirical Modified Atomic Orbital theory (MAOT) from n = 55. Very good agreements are seen between the present calculations and the available theoretical and experimental data. The present predicted data up to n = 55 may be of great importance to the atomic physics community, particularly in understanding the chemical evolution of Selenium in the Universe. Furthermore, the accurate data presented in this work may serve as a valuable guideline for future experimental investigations and alternative theoretical studies.