QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: Shan on November 25, 2014, 15:35

Title: Negetive Charging energies in SET
Post by: Shan on November 25, 2014, 15:35
Hi,

I'm working on Single Electron Transistor (SET) using ATK. while performing the calculation of benzene SET i observed some charging energies (Ionization energy and Electron affinity) are negative. ionization energy can be defined as the cost of removing an electron from the molecule and Electron affinity is the energy gained through adding an additional electron.
 
But my doubt is what does the negative ionization potential and electron affinity indicate.

Please clarify my doubt if u r aware of it, its a long sanding doubt of mine.


Thank You advance and thankyou for reading this post.
Title: Re: Negetive Charging energies in SET
Post by: kstokbro on November 27, 2014, 16:28
If you question relates to a tutorial, please specify which page and line in the tutorial
Title: Re: Negetive Charging energies in SET
Post by: Shan on November 28, 2014, 12:13
This post is in reference to your paper "First-principles modelling of molecular single-electron transistors" where in page no.9 you have shown charging energies of benzene and C60, out of which some are negative.

Hope u can clarify my doubt.

Awaiting your kind reply.


Title: Re: Negetive Charging energies in SET
Post by: Shan on December 1, 2014, 07:51
Some one please clarify my doubt...
Title: Re: Negetive Charging energies in SET
Post by: Shan on December 4, 2014, 14:14
Here in page number-9 of the attached document, negative charging energies have been reported. please observe them, and clarify what they indicate.
Title: Re: Negetive Charging energies in SET
Post by: Anders Blom on December 4, 2014, 15:24
Quote
The electron affinity of molecules is a complicated function of their electronic structure. For instance the electron affinity for benzene is negative, as is that of naphthalene, while those of anthracene, phenanthrene and pyrene are positive. In silico experiments show that the electron affinity of hexacyanobenzene surpasses that of fullerene.
http://en.wikipedia.org/wiki/Electron_affinity
Title: Re: Negetive Charging energies in SET
Post by: Shan on December 7, 2014, 21:32
Thank you Anders Sir...