Added check for qeq and option to turn off check

</H3>

<P><B>Syntax:</B>

</P>

<PRE>pair_style reax/c cfile 

<PRE>pair_style reax/c cfile keyword value 

</PRE>

<UL><LI>cfile = NULL or name of a control file 

</UL>

<PRE>one keyword value pair may be appended

keyword = <I>checkqeq</I> 

  <I>checkqeq</I> value = <I>yes</I> or <I>no</I> = whether or not to require qeq/reax fix 

</PRE>

</UL>

<P><B>Examples:</B>

</P>

<PRE>pair_style reax/c NULL

pair_style reax/c controlfile

pair_style reax/c controlfile checkqeq no

pair_coeff * * ffield.reax 1 2 2 3 

</PRE>

<P><B>Description:</B>

</P>

<P>The ReaxFF parameter files provided were created using a charge

equilibration (QEq) model for handling the electrostatic interactions.

Therefore it is highly recommended that the <A HREF = "fix_qeq_reax.html">fix

qeq/reax</A> command be used with pair style <I>reax/c</I>

Therefore, by default, LAMMPS requires that the <A HREF = "fix_qeq_reax.html">fix

qeq/reax</A> command be used with <I>pair_style reax/c</I>

when simulating a ReaxFF model, to equilibrate charge each timestep.

See the <A HREF = "fix_qeq_reax.html">fix qeq/reax</A> command for details.

</P>

<P>However, performing charge equilibration is not a prerequisite for

performing a ReaxFF simulation.  In this case, the static charges you

Using the keyword <I>checkqeq</I> with the value <I>no</I> 

turns off the check for <I>fix qeq/reax</I>,

allowing a simulation to be run without charge equilibration.

In this case, the static charges you

assign to each atom will be used for computing the electrostatic

interactions in the system.

See the <A HREF = "fix_qeq_reax.html">fix qeq/reax</A> command for details.

</P>

<P>The thermo variable <I>evdwl</I> stores the sum of all the ReaxFF potential

energy contributions, with the exception of the Coulombic and charge

<P><A HREF = "pair_coeff.html">pair_coeff</A>, <A HREF = "fix_qeq_reax.html">fix_qeq_reax</A>,

<A HREF = "pair_reax.html">pair_style reax</A>

</P>

<P><B>Default:</B> none

<P><B>Default:</B> The keyword default is checkqeq = yes.

</P>

<HR>

[Syntax:]

pair_style reax/c cfile :pre

pair_style reax/c cfile keyword value :pre

cfile = NULL or name of a control file :ul

one keyword value pair may be appended

keyword = {checkqeq} 

  {checkqeq} value = {yes} or {no} = whether or not to require qeq/reax fix :pre

:ule

[Examples:]

pair_style reax/c NULL

pair_style reax/c controlfile

pair_style reax/c controlfile checkqeq no

pair_coeff * * ffield.reax 1 2 2 3 :pre 

[Description:]

The ReaxFF parameter files provided were created using a charge

equilibration (QEq) model for handling the electrostatic interactions.

Therefore it is highly recommended that the "fix

qeq/reax"_fix_qeq_reax.html command be used with pair style {reax/c}

Therefore, by default, LAMMPS requires that the "fix

qeq/reax"_fix_qeq_reax.html command be used with {pair_style reax/c}

when simulating a ReaxFF model, to equilibrate charge each timestep.

See the "fix qeq/reax"_fix_qeq_reax.html command for details.

However, performing charge equilibration is not a prerequisite for

performing a ReaxFF simulation.  In this case, the static charges you

Using the keyword {checkqeq} with the value {no} 

turns off the check for {fix qeq/reax},

allowing a simulation to be run without charge equilibration.

In this case, the static charges you

assign to each atom will be used for computing the electrostatic

interactions in the system.

See the "fix qeq/reax"_fix_qeq_reax.html command for details.

The thermo variable {evdwl} stores the sum of all the ReaxFF potential

energy contributions, with the exception of the Coulombic and charge

"pair_coeff"_pair_coeff.html, "fix_qeq_reax"_fix_qeq_reax.html,

"pair_style reax"_pair_reax.html

[Default:] none

[Default:] The keyword default is checkqeq = yes.

:line