Dear all,

I want to use QMC in ALPS to simulate Bose-Hubbard model with NNN interaction, we know for NN interaction V, we can define V as following:

  <BONDTERM source="i" target="j">

    <PARAMETER name="V" default="0"/>

    V*n(i)*n(j)

  </BONDTERM>

Now I want to include NNN interaction, how can I define it? (source="i" target="?")

Best regards,

Tao Ying