TABLE OF CONTENTS

::pwtk::difden::segmentSpecialization

SYNOPSIS

proc ::pwtk::difden::segmentSpecialization {segmentIndex segmentSpec} {

PURPOSE

Set a special treatment of specified segment in "difden" calculation. For example, imagine to calculate the \Delta n(r) of CO molecule as \Delta n(r) = n(CO;r) - [n(C;r) + n(O;r)]. Oxygen atom is spin-polarized and hence require cooresponing specification in the input file, which is achieved with segmentSpecialization proc. The whole difden specification would look as follows: 

      DIFDEN {
        name(1)    = "CO"
        segment(1) = "all"
        weight(1)  = 1.0


        name(2)    = "C"
        segment(2) = 1
        weight(2)  = -1.0


        name(3)    = "O"
        segment(3) = 2
        weight(3)  = -1.0
     }


     ::pwtk::difden::segmentSpecialization 3 {
         SYSTEM { nspin = 2 }
     }
      
     ::pwtk::difden::run CO.difden

ARGUMENTS

SOURCE

    variable difden
    set difden(segmentSpec,$segmentIndex) $segmentSpec
}