File <file>.brz

A file of the type <file>.brz is written by MOPAC and read by BZ.  It contains all the information needed for the construction of the Brillouin zone, and is not intended to be read by a user.  However, for users who would like to examine this file, the following description of the contents  is provided:

 

First line (Four integers and the letter T or F)

For electronic work, NORBS: Number of orbitals (one integer).  for phonon work, 3*NATOMS.
Number of mers in each direction (three integers)
BCC (logical.  "T" if BCC is present, "F" otherwise)

Next block (A large number of real numbers)

For electronic work, the Fock matrix, lower half triangle, (real, (NORBS*(NORBS+1))/2 data); for phonon work, the mass-weighted Hessian (real, (NATOMS*3*(NATOMS*3+1))/2 data), where NORBS = number of atomic orbitals in the system, and NATOMS = number of atoms in the system.)
Translational vector lengths (9 real numbers) For a polymer, ignore the last six data, for a layer, ignore the last three data.

Next block (Two integers, then more real numbers)

Number of dimension (integer) If  value = 1, then a polymer; if 2, then a layer, and if 3 then a solid.
Number of atoms (integer)
Cartesian coordinates (real, 3 times number of atoms)

Next block (A large number of integers)

For electronic work: the orbital counters (integer, 2 times number of atoms) These are the starting and ending orbital indices for each atom. For phonon work, the series: 1, 3, 4, 6, 7, 9, etc. or (i - 2, i, i = 1:(number of atoms)).  These indicate the degrees of freedom associated with each atom.
 

How to make <file>.brz

The file <file>.brz is generated when a MOPAC data set that contains keywords MERS, and possibly other keywords, is run. For electronics, any keywords except MOZYME that result in a normal output, i.e., an output that includes the text "FINAL HEAT OF FORMATION" should also be present.  For example, keywords such as FORCE and 0SCF should not be present.  For phonon work FORCE and ISOTOPE or RESTART should also be present. Keyword MERS should always be added by running MAKPOL, it should not be typed in "by hand."