Page 224 - Strategies and Applications in Quantum Chemistry From Molecular Astrophysics to Molecular Engineer
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ELECTRONIC CHARGE DENSITY OF QUANTUM SYSTEMS                            207




                       with





                       A series of manipulations [see Appendix B, eq. (B.4)] allows the function  to  be
                       expressed as follows









                       where we have set


                       and Ai[x] denotes the Airy function of argument x [33].
                       The replacement  of  the result  for    eq.  (2.10),  into eq.  (2.8) yields  for the

                       electronicdensity




                       where










                       The expression for      can be elaborated rather simply, [see Appendix C, eq. (C.4)]








                       Indefinite integrals involving products of Airy functions and/or their derivatives can be
                       evaluated without many difficulties [34]. Thus,
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