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Molecular hardness and Roothaan energy equations

✍ Scribed by Mario Giambiagi; Myriam Segre De Giambiagi; José Maria Pires

Publisher
Elsevier Science
Year
1988
Tongue
English
Weight
356 KB
Volume
152
Category
Article
ISSN
0009-2614

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✦ Synopsis

Using the dependence of the electronic energy on MU occupation numbers, it is shown that for an N-electron species the hardness depends on whether N is even or odd. For odd N, we find that the usual I-A expression is appropriate. For even N, the hardness is given by the interaction between electrons in the HOMO and the LUMO. We show the results of calculations for this last case and compare them with results from others.

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