Hi all,

I'm trying to run fulldiag in python on a spin model that involves terms like Sx(i)Sy(j). I can define Sy using the imaginary unit uppercase "I" with no immediate error message. I can also use terms such as Sy(i)Sy(j). (My Hamiltonian definition includes the line <PARAMETER name="COMPLEX" default="True"/> .)

However, if I try to use a term with a complex coefficient such as (1+I), or if I try to have an imaginary term in the Hamiltonian such as Sx(i) Sy(j), I get an "Execution error in evaluateFulldiagVersusT".

Alternatively, if I don't use evaluateFulldiagVersusT, but instead set writexml=True in the options for running fulldiag, then I get no error message but the fulldiag program appears not to run (and no xml file is created) if I have terms with complex/imaginary coefficients.

What can I do to include terms such as Sx+Sy in my Hamiltonian?

Thanks, Itamar