Sorry, I don't know your spin model "high-temperature superconductor La2CuO4", and as the model in the XML file is defined it does not make much sense since for spin S=1/2 as defined in the model, the operators (S^z)^2, (S^x)^2 and (S^y)^2 are all identity operators.

On Apr 13, 2012, at 4:23 PM, konefvitbka53@gmail.com wrote:

Model high-temperature superconductor La2CuO4

<model.xml>