Question about SpinW manual and pyspinw (ADDCOUPLING)

[tombadmanship]

I have been figuring out how to use this program over the past couple of days. I can't get the 'addcoupling' function to work for my system in pyspinw 3.0.0. Specifically, I'm trying to generate an antiferromagnetic coupling between 16 atoms using addmatrix and gencoupling.

here is my code for generating the negative J coupling (is it correct?):

H_sys.addmatrix('value',-np.eye(3),'label','J1')

Here is my code for generating the coupling:

H_sys.addcoupling('J1',1)

Thank you.

[wardsimon]

Hi,

The code for generating the negative couplings is correct but adding it to the bond should be:

H_sys.addcoupling('mat','J1','bond',1.)

Simon