HELIUMATOM
Helium atom
A helium atom is an atom of the chemical element helium. Helium is composed of two electrons bound by the electromagnetic force to a nucleus containing two protons along with either one or two neutrons, depending on the isotope, held together by the strong force. Unlike for hydrogen, a closed-form solution to the Schrödinger equation for the helium atom has not been found. However, various approximations, such as the Hartree-Fock method, can be used to estimate the ground state energy and wavefunction of the atom.The above text is a snippet from Wikipedia: Helium atom
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