QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: SandraRG on August 3, 2017, 17:01

Title: Counterpoise correction
Post by: SandraRG on August 3, 2017, 17:01

Hello everyone,

Is it possible, and/or  necessary to include the counterpoise correction in the initial self-consistent field calculation in a molecular junction?? , and How is it implemented?

I would like to calculate the transmission spectrum and current-voltage curves for a densely packed molecular junction, and I do not want to run the risk of suffer BSSE.

Thanks in advance,

Title: Re: Counterpoise correction
Post by: Daniele Stradi on August 4, 2017, 10:42

Hi,

by "initial self-consistent field calculation", do you mean the geometry optimization?

You can check this tutorial for a detailed explanation of how the counterpoise correction works in ATK:

http://docs.quantumwise.com/tutorials/dispersion_corrections_and_bsse/dispersion_corrections_and_bsse.html

Regards,
Daniele,

Title: Re: Counterpoise correction
Post by: SandraRG on August 4, 2017, 14:52

Hi,
Thanks for the link.
No, I mean an initial self-consistent field calculation without geometry optimization, using a fixed geometry to obtain the initial electron density of the system.
In the case of  single molecule-junction, I did not apply any kind of correction.
When I reduce the unit cell to obtain a more densely packed monolayer, in order to account the collective electrostatic effects between molecules,  I do not know if it is necessary to include some correction or not.
1.- If basis set superposition error (BSSE)appear, Does the output file give a error message by default???
2.-Regarding to the tutorial, I have to introduce both: the conterpoise correction and theD2 dispersion correction, it is right??
Thanks again.