Dear all
If I want to study bilayer Heisenberg model, what's wrong with the following Hamiltonian (the error message read " bad lexical cast: source type value could not be interpreted as target ")? Many thanks in advance.
<PARAMETER name="Az" default="Q"/> <PARAMETER name="Axy" default="Az"/> <PARAMETER name="Q" default="1"/> <PARAMETER name="A1z" default="Q2"/> <PARAMETER name="A1xy" default="Q3"/> <PARAMETER name="h" default="h1"/> <BASIS ref="spin"/> <SITETERM site="i"> -h1*Sz(i) </SITETERM> <BONDTERM type="1" source="i" target="j"> Az*Sz(i)*Sz(j)+Axy*exchange_xy(i,j) </BONDTERM> <BONDTERM type="0" source="i" target="j"> A1z*Sz(i)*Sz(j)+A1z*A1xy*exchange_xy(i,j) </BONDTERM>
Sincerely, Fu-Jiun