Indeed, please look at the lattices you use. The anisotropic aquare lattice has two types of bonds and thus needs hoppings t0 (or t) and t1

Matthias

On 18 Apr 2009, at 07:47, sinan bulut wrote:

I don't know exactly but the difference might be that in the isotropic case the magnitude of the basis vectors are the same while it is not for the anisotropic case.

On Sat, Apr 18, 2009 at 8:05 AM, khalid hassan mkhloane@yahoo.com wrote:

Dear alps team I got the results. the only mistake I was making is to use anisotropic lattice instead of square lattice.

what is difference in anisotropic lattice with L=2 W=2 and square lattice with L=2.

thanks

Best regards Khalid Loane