QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: abhishek77492652 on November 8, 2017, 15:12

Title: Extended Huckel Basis set
Post by: abhishek77492652 on November 8, 2017, 15:12

How to set the basis set in extended Huckel model and what should be the corresponding vacuum level value ?

Title: Re: Extended Huckel Basis set
Post by: Petr Khomyakov on November 8, 2017, 16:44

The Huckel model parameters is set in the corresponding Calculator in the VNL.  If you do calculations for a bulk system, there is no vacuum level, since there exists no vacuum in an infinite periodic solid. One should, for example, create a surface to have it.

Title: Re: Extended Huckel Basis set
Post by: abhishek77492652 on November 8, 2017, 17:21

But if we work on device then we need the vacuum level value . How to set the vacuum level for device consists of MoS2 (what is the value of vacuum level for Mo and S) ?

Title: Re: Extended Huckel Basis set
Post by: Petr Khomyakov on November 10, 2017, 13:38

I believe the vacuum level is determined during self-consistently calculation of your device.  I do not think you can separably define two vacuum levels for Mo and S in the MoS2-based device. It is possible for single, isolated atoms that do not interact with each other.