QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: beauyy on February 6, 2015, 04:33

Title: hard to converge in IV curves of black phosphorus with F4TCNQ
Post by: beauyy on February 6, 2015, 04:33

Dear sir,
  I am calculating the I-V curves of black phosphorus with F4TCNQ. The transmission calculation is converged under 0 V, however it is different to converge under other bias. What is the problem?
  ATK 11.8.2 cannot calculate the transmission of black phosphorus under bias > 1.0 V, however ATK 14.2 can do it. Is it a bug in ATK 11.8.2? How can solve this problem?
  I have attached the IV calculation .py document.

Title: Re: hard to converge in IV curves of black phosphorus with F4TCNQ
Post by: Anders Blom on February 6, 2015, 12:41

Poor convergence is not a "bug", but during the last 3 years we have of course been able to tune and improve the algorithms to make convergence better.