QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: Dhirendra on November 23, 2016, 16:23

Title: MGGA formulation
Post by: Dhirendra on November 23, 2016, 16:23

In the original paper from Tran and Blaha, they use sqrt(5/12) factor. But QuantumWise is using sqrt(4/12) factor in their formulation http://docs.quantumwise.com/tutorials/inas_2d_mgga/inas_2d_mgga.html.
Which is the implemented version?

Title: Re: MGGA formulation
Post by: Petr Khomyakov on November 24, 2016, 10:24

This is a typo in the tutorial. Thanks for spotting it. But it is implemented correctly in the ATK code, where the factor of sqrt(5/12) was used in the formula for the MGGA-TB09 exchange potential, in consistency with the original work by Tran and Blaha.