Subject: Negative Ionization Potential?

From: Carolina <[email-masked]>
Date: Wed, 15 Dec 93 18:24:50 CST

Dear Netters:

While taking a course on Semiempirical methods, I was given the assigment
of determining the effect of increasing the charge of a polyanionic 
molecule on its Ionization potential.

So, according to Koopman's theorem I found (with AM1) that:

Neutral molecule	HOMO=-10.456 eV		thus	IP=+10.456 eV
With charge of -6	HOMO=-0.367 eV			IP=+0.367
with charge of -12	HOMO=+8.879 eV			IP=-8.879

The first two make sense to me, because according to the IP definition
it will be the energy we need for infinite removal of the ionized
electron.

However, I do not understand the significance of a negative ionization
potential; or maybe I do not understand what process the ioinization
potential refers to.

Please help!

Thanks a million.

--

___________________________________________________________________
			CAROLINA GODOY-ALCANTAR
Facultad de Ciencias
Universidad del Edo. de Morelos
Chamilpa, Morelos.

email:    [email-masked]