Guseinov, Israfil Isa2025-01-272025-01-2720070259-97911572-8897https://doi.org/10.1007/s10910-006-9154-1https://hdl.handle.net/20.500.12428/22949The simpler formulas are derived for the complete orthonormal sets of exponential- type orbitals, momentum space orbitals and hyperspherical harmonics and their expansion and one-range addition theorems. The continuum states are not properly included in these functions. The analytical formulas are also obtained for the overlap integrals over Psi(alpha)-ETOs, their extensions to momentum and four-dimensional spaces and STOs with the same screening constants using addition and expansion theorems derived in this paper. The complete orthonormal sets of functions and their expansion and one-range addition theorems obtained can be useful in the study of different quantum mechanical problems when the coordinate, momentum or four-dimensional spaces employed.eninfo:eu-repo/semantics/closedAccessexponential-type orbitalsmomentum space orbitalshyperspherical harmonicsone-range addition theoremsArticle424991100110.1007/s10910-006-9154-1Q2WOS:0002498089000202-s2.0-38149089597Q2