diff --git a/doc/_sources/bond_write.txt b/doc/_sources/bond_write.txt new file mode 100644 index 0000000000..66cf5884bc --- /dev/null +++ b/doc/_sources/bond_write.txt @@ -0,0 +1,74 @@ +.. index:: bond_write + +bond_write command +================== + +Syntax +"""""" + +.. parsed-literal:: + + bond_write btype N inner outer file keyword itype jtype + +* btype = bond types +* N = # of values +* inner,outer = inner and outer bond length (distance units) +* file = name of file to write values to +* keyword = section name in file for this set of tabulated values +* itype,jtype = 2 atom types (optional) +* + +Examples +"""""""" + +.. parsed-literal:: + + bond_write 1 500 0.5 3.5 table.txt Harmonic_1 + bond_write 3 1000 0.1 6.0 table.txt Morse + +Description +""""""""""" + +Write energy and force values to a file as a function of distance for +the currently defined bond potential. This is useful for plotting the +potential function or otherwise debugging its values. If the file +already exists, the table of values is appended to the end of the file +to allow multiple tables of energy and force to be included in one +file. + +The energy and force values are computed at distances from inner to +outer for 2 interacting atoms forming a bond of type btype, using the +appropriate :doc:`bond_coeff ` coefficients. N evenly spaced +distances are used. + +For example, for N = 7, inner = 1.0, and outer = 4.0, +values are computed at r = 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0. + +The file is written in the format used as input for the +:doc:`bond_style ` *table* option with *keyword* as the +section name. Each line written to the file lists an index number +(1-N), a distance (in distance units), an energy (in energy units), +and a force (in force units). + +Restrictions +"""""""""""" + + +All force field coefficients for bond and other kinds of interactions +must be set before this command can be invoked. + +Due to how the bond force is computed, an inner value > 0.0 must +be specified even if the potential has a finite value at r = 0.0. + +Related commands +"""""""""""""""" + +:doc:`bond_style table `, +:doc:`bond_style `, :doc:`bond_coeff ` + +**Default:** none + + +.. _lws: http://lammps.sandia.gov +.. _ld: Manual.html +.. _lc: Section_commands.html#comm