In the equation for an orbital, we want to reduce the number of variables from many (in a multi-electronic case) to one. This is done by assuming that each electron moves in an average field created by all the other electrons. For example, one of the electrons in He, say electron 1 may be thought of moving in a field of the nucleus plus the average field created by the second electron.
(6.3)
The three terms in the left refer to the kinetic energy, electron nuclear attraction energy and the effective field on electron 1 due to electron 2 and E1 is the orbital energy. The effective field at r1 is obtained by averaging the energy between electron1 at r1 and electron 2 at r2 by allowing the second electron at r2 to cover the whole space
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(6.4)
By the same analogy, electron 2 moves in an average field created by electron 1. These equations for electron 1 and electron 2 are solved iteratively starting with assumed formulae for and and the iterations (repeated solutions) are stopped when the average field created by electron 1 on electron 2 is consistent with the average field created by electron 2 on electron 1. These orbitals are called self-consistent orbitals. This method is referred to as the self-consistent field (SCF) method and forms a very important method for studying atomic and molecular structure.
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and 
and the iterations (repeated solutions) are stopped when the average field created by electron 1 on electron 2 is consistent with the average field created by electron 2 on electron 1. These orbitals are called self-consistent orbitals. This method is referred to as the self-consistent field (SCF) method and forms a very important method for studying atomic and molecular structure. 
