Title




Forcebalance and differential equation for the groundstate electron density in atoms and molecules


Author






Abstract




Holas and March (1995) established a forcebalance equation from the manyelectron Schrodinger equation. Here, we propose this as a basis for the construction of a (usually approximate) differential equation for the groundstate electron density. By way of example we present the simple case of twoelectron systems with different external potentials bur with weak electronelectron Coulomb repulsion lambda e(2)/r(12). In this case firstorder RayleighSchrodinger (RS) perturbation theory of the groundstate wave function is known to lead to a compact expression for the firstorder density matrix gamma(r, r') in terms of its diagonal density rho(r) and the density corresponding to lambda = 0. This result allows the forcebalance equation to be written as a thirdorder linear, differential homogeneous equation for the groundstate electron density rho(r). The example of the twoelectron Hookean atom is treated: For this case one can also transcend the firstorder RS perturbation theory and get exact results for discrete choices of force constants (external potential). (C) 2000 John Wiley & Sons, Inc. 


Language




English


Source (journal)




International journal of quantum chemistry.  New York, N.Y.


Publication




New York, N.Y.
:
2000


ISSN




00207608


Volume/pages




77
:4
(2000)
, p. 716720


ISI




000085977200004


Full text (Publisher's DOI)






Full text (publisher's version  intranet only)





