Dear ATK Forum,

I am interested in calculating transport with noncollinear spin and spin-orbital coupling.

I found the relevant tutorial, at

Introduction to noncollinear spin | QuantumATK R-2020.09 Documentation.

In this example, it sets up noncollinear calculation from collinear one.

The only difference is to change initial spin configuration from parallel (or anti-parallel)

to a rotated one.

My questions are

(1) after SCF, will the spin configuration go back to collinear case?

(2) there is one ground state only for carbon chain. The ground state is either collinear

spin or noncollinear. spin. Why can we have both collinear transport and noncollinear transport?

(3) without introducing spin-orbital coupling, we still can get noncollinear spin?

(4) is the spin orbital coupling (SOC) activated by just changing the exchangeâ€“correlation method

and pseudopotentials? Is there a paper about how does SOC implement in ATK?

Thanks,

Jie