Very werid problem!

[hkuieagle]

Hi all. I encountered the problem when I was doing some calculations on two probe system of graphene.Then to be simple,I take an experiment on Lih2Li system.Below is the description of the problem:
There are two scripts in the attachment which are copyed from the ATK manual , the ONLY difference between them is in the "unit_cell"(I reverse the order of A and B vertor). Since  it's symmetrical between A and B,I don't think it'll make any difference. But the results differs by a mile!
For lih2li-setup-1.py : the current is 1.57e-05
For lih2li-setup-2.py : the current is 1.69e-12
Well ,How to explain ?

bwt: ATK 2008.02.0 Linux-i686 build 13600 2008-03-03

[zdhlover]

Do you think you can build a strange bulk structure:[[  0. ,   8.7,   0. ],
                                                                          [  8.7,   0. ,   0. ],
                                                                          [  0. ,   0. ,  11.6]]*Angstrom as the second script ?

you'd better check whether your two-probe system is correct or not at first.

[Anders Blom]

The systems are not 100% equivalent: one is right-handed and one is left-handed. You had better always make your unit cell right-handed to avoid problems.

[hkuieagle]

Well, I don't think we can tell the right-hand unit-cell from the left-hand in reality (even I don't know how to create the difference between them in lab).

[Anders Blom]

True. But numerically there's a difference.

[youngjfly]

true