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                                                     RPS: PSP0007 - Science-at-Nanoscale
                   June 9, 2009
                                                  3.3. Hydrogen-like Atoms: Orbitals and Atomic Structures
                                   Table 3.1 First 10 orbitals and the corresponding
                                   quantum numbers of a hydrogen atom.
                                        n
                                               l
                                                             m
                                                                            s
                                   1s
                                                             0
                                               0
                                        1
                                                                        1/2, −1/2
                                   2s
                                               0
                                        2
                                                             0
                                                           1, 0, −1
                                        2
                                               1
                                   2p
                                                                        1/2, −1/2
                                                                        1/2, −1/2
                                               0
                                   3s
                                        3
                                                             0
                                               1
                                   3p
                                                                        1/2, −1/2
                                        3
                                                           1, 0, −1
                                               2
                                                                        1/2, −1/2
                                                        2, 1, 0, −1, −2
                                   3d
                                        3
                                                                        1/2, −1/2
                                       4
                                                             0
                                   4s
                                               0
                                                                        1/2, −1/2
                                                           1, 0, −1
                                               1
                                       4
                                   4p
                                               2
                                                                        1/2, −1/2
                                                        2, 1, 0, −1, −2
                                   4d
                                       4
                                       4
                                   4f
                                               3
                                                      3, 2, 1, 0, −1, −2, −3
                                                                        1/2, −1/2
                               In spherical coordinates, Eq. (3.56) takes the form
                                                                                   2
                                2

                                                                            1
                                                      1

                              h



                                     1 ∂
                                                           ∂
                                                                   ∂
                                             ∂
                                                                                  ∂
                                           2
                                          r
                                                              sin θ
                           −
                                                +
                                     2
                                 2
                                                                                    2
                                                   2
                                                                             2
                                    r ∂r
                                                                          2
                                            ∂r
                                                                         r sin (θ) ∂φ
                             8mπ
                                                                  ∂θ
                                                  r sin(θ) ∂θ
                                     2
                                   Ze
                                                                                   (3.62)
                                −
                                       ψ = Eψ
                                  4πε 0 r
                               We can re-write the wavefunction as a product of two functions,
                             one that depends only on the distance r and the other one that only
                             depends on the orientation, i.e. θ, φ.
                                                ψ(r, θ, φ) = R(r)Y(θ, φ)     + 1/2, −1/2  (3.63) ψ  53  ch03
                               Here R(r) is known as the Radial Wavefunction and Y(θ, φ) is
                             known as the Spherical Harmonic. The radial function depends
                             on the potential energy. On the other hand, the spherical harmonic
                             does not depend on the particular form of the potential energy if
                             the potential energy is only a function of r. The spherical harmonic
                             satisfies the following equation for the quantum operator for the
                                                             2
                             square of the angular momentum, L :
                                                  2
                               |Angular momentum| operator
                                                        h 2
                                                  2
                                                 L Y =    2  l(l + 1)Y            (3.64)
                                                       4π
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