Release64:Qmmm link ecp

From NWChem

link_ecp  <(auto||user) default auto>

This directive specifies ECP basis set on fluoride link atoms. If set to auto the ECP basis set given by Zhang, Lee, Yang for 6-31G* basis.35.2 will be used. Strictly speaking, this implies the use of 6-31G* spherical basis as the main basis set. If other choices are desired then keyword user should be used and ECP basis set should be entered separatelly following the format given in section 8. The name tag for fluoride link atoms is F_L.