QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: bfazi on January 3, 2017, 18:29

Title: Calculation error
Post by: bfazi on January 3, 2017, 18:29

Hi,

I want to calculate the transmission spectrum of G-BN-G as the attached script. But I got the following error:

"** Back Engine Exception : No dispersion of the ComplexBandstructure as there is no interaction between neighbouring cells.
A potential source of this error could be vacuum in the z-axies or when a tight-binding basis set is used outside of its application domain, for example when using a ZnTe basis set for a pure Zn calculation.
** Location of Exception : electrodeutils.cpp:457"

Why did the error happen? and how can I correct it?

Thanks

Title: Re: Calculation error
Post by: Anders Blom on January 3, 2017, 21:02

The answer is given in the error message.

Title: Re: Calculation error
Post by: Anders Blom on January 3, 2017, 21:31

Quote from: AHB on January  3, 2017, 18:29

"** Back Engine Exception : No dispersion of the ComplexBandstructure as there is no interaction between neighbouring cells.
A potential source of this error could be vacuum in the z-axies

Your system is not periodic in Z

Title: Re: Calculation error
Post by: Anders Blom on January 3, 2017, 23:44

Nope. Your structure is not periodic in C so that doesn't help. You should reorient the system (swap axes) so that C corresponds to a periodic direction (in-plane). I suggest you consult the tutorial describing this: http://docs.quantumwise.com/tutorials/transmission_gr_mos2