Update docs: bond_fene_expand

doc/src/Eqs/bond_fene_expand.tex

@@ -1,13 +0,0 @@
-\documentclass[12pt]{article}
-
-\begin{document}
-
-$$ 
-  E = -0.5 K R_0^2
-  \ln \left[1 -\left( \frac{\left(r - \Delta\right)}{R_0}\right)^2 \right] + 
-  4 \epsilon \left[ \left(\frac{\sigma}{\left(r - 
-      \Delta\right)}\right)^{12} - \left(\frac{\sigma}{\left(r - 
-      \Delta\right)}\right)^6 \right] + \epsilon
-$$
-
-\end{document}

doc/src/bond_fene_expand.rst

@@ -1,16 +1,16 @@
-.. index:: bond\_style fene/expand
+.. index:: bond_style fene/expand
 
-bond\_style fene/expand command
-===============================
+bond_style fene/expand command
+==============================
 
-bond\_style fene/expand/omp command
-===================================
+bond_style fene/expand/omp command
+==================================
 
 Syntax
 """"""
 
 
-.. parsed-literal::
+.. code-block:: LAMMPS
 
    bond_style fene/expand
 
@@ -18,7 +18,7 @@ Examples
 """"""""
 
 
-.. parsed-literal::
+.. code-block:: LAMMPS
 
    bond_style fene/expand
    bond_coeff 1 30.0 1.5 1.0 1.0 0.5
@@ -28,29 +28,30 @@ Description
 
 The *fene/expand* bond style uses the potential
 
-.. image:: Eqs/bond_fene_expand.jpg
-   :align: center
+.. math::
+
+   E = -0.5 K R_0^2 \ln \left[1 -\left( \frac{\left(r - \Delta\right)}{R_0}\right)^2 \right] + 4 \epsilon \left[ \left(\frac{\sigma}{\left(r - \Delta\right)}\right)^{12} - \left(\frac{\sigma}{\left(r - \Delta\right)}\right)^6 \right] + \epsilon
+
 
 to define a finite extensible nonlinear elastic (FENE) potential
 :ref:`(Kremer) <feneexpand-Kremer>`, used for bead-spring polymer models.  The first
 term is attractive, the 2nd Lennard-Jones term is repulsive.
 
 The *fene/expand* bond style is similar to *fene* except that an extra
-shift factor of delta (positive or negative) is added to *r* to
+shift factor of :math:`\Delta` (positive or negative) is added to :math:`r` to
 effectively change the bead size of the bonded atoms.  The first term
-now extends to R0 + delta and the 2nd term is cutoff at 2\^(1/6) sigma
-+ delta.
+now extends to :math:`R_0 + \Delta` and the 2nd term is cutoff at :math:`2^\frac{1}{6} \sigma + \Delta`.
 
 The following coefficients must be defined for each bond type via the
 :doc:`bond\_coeff <bond_coeff>` command as in the example above, or in
 the data file or restart files read by the :doc:`read\_data <read_data>`
 or :doc:`read\_restart <read_restart>` commands:
 
-* K (energy/distance\^2)
-* R0 (distance)
-* epsilon (energy)
-* sigma (distance)
-* delta (distance)
+* :math:`K` (energy/distance\^2)
+* :math:`R_0` (distance)
+* :math:`\epsilon` (energy)
+* :math:`\sigma` (distance)
+* :math:`\Delta` (distance)
 
 
 ----------
@@ -106,8 +107,3 @@ Related commands
 
 
 **(Kremer)** Kremer, Grest, J Chem Phys, 92, 5057 (1990).
-
-
-.. _lws: http://lammps.sandia.gov
-.. _ld: Manual.html
-.. _lc: Commands_all.html