Dear Alps users,

I want to make a spin_y operator in the spin basis. 

I know that spin x can be constructed in this way:
<SITEOPERATOR name="Sx" site="x">
  1/2*(Splus(x)+Sminus(x))
</SITEOPERATOR>

To get Sy i need to have complex i in the operator, but I am unsure of how to express it.

Best regards,
Simon Ydman