Commit1 JT 070918

one or more keyword/value pairs may be appended :l

keyword = {type} or {type/fraction} or {mol} or {x} or {y} or {z} or \

          {charge} or {dipole} or {dipole/random} or {quat} or \

          {spin} or {spin/random} or {quat} or \

          {quat/random} or {diameter} or {shape} or \

          {length} or {tri} or {theta} or {theta/random} or \

          {angmom} or {omega} or \

  {dipole/random} value = seed Dlen

    seed = random # seed (positive integer) for dipole moment orientations

    Dlen = magnitude of dipole moment (dipole units)

  {spin} values = g x y z

    g = magnitude of magnetic spin vector (in Bohr magneton's unit)

    x,y,z = orientation of magnetic spin vector

    any of x,y,z can be an atom-style variable (see below)

  {spin/random} value = seed Dlen

    seed = random # seed (positive integer) for magnetic spin orientations

    Dlen = magnitude of magnetic spin vector (in Bohr magneton's unit)

  {quat} values = a b c theta

    a,b,c = unit vector to rotate particle around via right-hand rule

    theta = rotation angle (degrees)

many processors are being used.  This keyword does not allow use of an

atom-style variable.

Keyword {spin} uses the specified g value to set the magnitude of the

magnetic spin vectors, and the x,y,z values as components of a vector 

to set as the orientation of the magnetic spin vectors of the selected 

atoms.  

Keyword {spin/random} randomizes the orientation of the magnetic spin

vectors for the selected atoms and sets the magnitude of each to the 

specified {Dlen} value.  

Keyword {quat} uses the specified values to create a quaternion

(4-vector) that represents the orientation of the selected atoms.  The

particles must define a quaternion for their orientation

This directory contains examples and applications of the SPIN package

=====================================================================

- the iron, cobalt_hcp, cobalt_fcc and nickel directories provide 

examples of spin-lattice calculations.

- the bfo repository provides an example of spin dynamics calculation

performed on a fixed lattice, and applied to the multiferroic 

material bismuth-oxide. 

- the read_restart directory provides examples allowing to write or 

read data files, and restart magneto-mechanical simulations.  

- vizualization of the dump files can be achieved using Ovito or 

VMD. See the vmd repository for help vizualizing results with VMD. 

** Note, the aim of this repository is mainly to provide users with

examples. Better values and tuning of the magnetic and mechanical 

interactions can be achieved for more accurate materials 

simulations. **