Dear Matthias Troyer and ALPS developers,

I've been testing the TEBD routines by using python programs as the ones present in the tutorials. I wanted to go further from what we can find in such tutorials because of my research interests and according to the possibilities of the TEBD routines of the ALPS 2.0 illustrated in the paper: The ALPS project release 2.0: open source software for strongly correlated systems.

What I just found is that if I use a general spin value in the spin chains (TEBD-02) let say S, the initial "kink" state of the chain does not represent a general down,down,....,up,up.... states for the system but just a partial spin flit is performed in the initial aligned state.

I check the numerical results at the very initial moment of the spin dynamics calculation and the "kink" state for a S system turns out to be S S S......, S-0.5 S-0.5 S-0.5 ....... which means a 0.5 less in the second part of the vector state instead of being S S S......, -S -S -S as it should be.

I read the ALPS web page and paper and I couldn't see anything expressing that the TEBD routines are just working for spin 1/2 in the case of the kink state. If it is so, how can I modify such a situation in order to work with different spin values?. The ALPS paper says that the TEBD routines should work for the "spin" models in the ALPS and such models allow modifications of the spin value.

Thanks for your answer.

JM.