quantum-espresso/doc-def/INPUT_BANDS.def

input_description -distribution {Quantum Espresso} -package PWscf -program bands.x {

    toc {}

    intro {
	Purpose of bands.x:
	    Rewrite the bands ordering them using the overlap 
	    of the wave-functions on neighbor k points
	    and calculate properties of each eigen-function.

	Presently it can calculate:

	   (a) The expectation value of the spin operator on each spinor
               wave-function.
           (b) The symmetry properties of each wavefunction. With this option
               the bands are not ordered according to the overlap.

        The input data of this program are read from standard input
        or from a file and have the following format:
	

        Structure of the input data:
	============================

	   &INPUTPP
	     ...
	   /
    }

    namelist INPUTPP {

	var prefix -type CHARACTER {   
	    info {
		prefix of files saved by program pw.x
	    }
	}

	var outdir -type CHARACTER {     
	    info {
		temporary directory where pw.x files resides
	    }
	}

	var filband -type CHARACTER {     
	    info {
		file "filband" contains the bands
	    }
	}

	var spin_component -type INTEGER { 
	    info {
		In the lsda case select:
		
		   1 = spin-up
		   2 = spin-down
	    }
	}

	dimension lsigma(i)  -start 1 -end 3 -type LOGICAL { 
	    info {
		If true writes a file filband.i with the expectation
		values of the spin operator on the spinor wave-functions.
		(only in the noncollinear case).
	    }
	}

	var lsym -type LOGICAL {
	    info {
		If .true. the bands are classified according to the
		irreducible representations of the small group of k. A
		file "filband".rap with the same format of "filband"
		is written.
	    }
	}
	 
	var no_overlap -type LOGICAL { 
	    default { .false. }
	    info {		
		If .true. writes the eigenvalues in the output file
		without changing their order.

	    }
	}
           
	vargroup -type INTEGER {
	    var firstk
	    var lastk 
	    info {		
		if lsym=.true. makes the symmetry analysis only for k
		points between firstk to lastk		
	    }
	}
    }
}