Page 113 - Bruno Linder Elementary Physical Chemistry
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August 18, 2010 11:36      9in x 6in     b985-ch09     Elementary Physical Chemistry





                               98                   Elementary Physical Chemistry

































                                                      Particle-in-a-box wave-functions.
                                             Fig. 9.1
                                                              + + +
                               9.2. Hydrogenic Atoms (H, He ,Li    2+ + + ,etc.)
                               The Schr¨dinger equation yields the following solution:
                                      o
                                                                 2
                                                      E n = −hcZ R H /n 2                  (9.4)
                               where Z is the atomic number and R H is the Rydberg constant for the
                               Hatom,
                                                                4
                                                       R H = m e e /8 ε 0 h 2              (9.5)
                               m e being the mass of the electron and ε 0 the vacuum permeability. Most
                                                     2
                               often, the combination Z is used where R defines the particle Rydberg
                               constant.
                                  The hydrogenic wave-functions are characterized by 3 quantum
                               numbers:

                               1) The principle quantum number, n =1, 2,..., which determines the
                                 energy of the electron in the atom.
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