[Wannier] Problem with the physical interpretation of hr file data

[Christian helman]

Hello
I successfully converge my paramagnetic system (no spin polarization,
neither s-o). All convergence parameters are according to the
suggestions made by the manual and tutorials. Then I plot the wannier
functions and are as expected, for example one with dxy symmetry,
looks beautiful and correctly aligned with the axis.
However, if I take a look to the hr file, the hamiltonian bracket
between this WF and the same WF but in the other cell (its the 2nd
neighbor) has a negative value (imaginary part equal to zero).

That is, < dxy(R=000) | H | dxy(R=010) > = -0.1 .

There is a physical problem here, the dxy lobes superpose with
different signs, then the resulting hamiltonian value should be
positive.
Any hint?
Is my interpretation wrong?
Thanks in advance

-- 
Dr. Christian Helman
Departamento de Neutrones y Reactores
Centro Atómico Bariloche -CNEA
Ezequiel Bustillos 9,500 Km - CP 8400
San Carlos de Bariloche
Provincia de Rio Negro, Argentina
Tel:++54-294-444-5100 int 5308