diff --git a/doc/Eqs/angle_fourier.jpg b/doc/Eqs/angle_fourier.jpg
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diff --git a/doc/Eqs/angle_fourier.tex b/doc/Eqs/angle_fourier.tex
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+++ b/doc/Eqs/angle_fourier.tex
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+\documentclass[12pt]{article}
+
+\begin{document}
+
+$$
+   E = K [C_0 + C_1 \cos ( \theta) + C_2 \cos( 2 \theta) ] 
+$$
+
+\end{document}
diff --git a/doc/Eqs/angle_fourier_simple.jpg b/doc/Eqs/angle_fourier_simple.jpg
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diff --git a/doc/Eqs/angle_fourier_simple.tex b/doc/Eqs/angle_fourier_simple.tex
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index 0000000000..3228315a13
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+++ b/doc/Eqs/angle_fourier_simple.tex
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+\documentclass[12pt]{article}
+
+\begin{document}
+
+$$
+   E = K [ 1.0 + c \cos ( n \theta) ] 
+$$
+
+\end{document}
diff --git a/doc/Eqs/angle_quartic.jpg b/doc/Eqs/angle_quartic.jpg
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diff --git a/doc/Eqs/angle_quartic.tex b/doc/Eqs/angle_quartic.tex
new file mode 100644
index 0000000000..ff9ff9a7dc
--- /dev/null
+++ b/doc/Eqs/angle_quartic.tex
@@ -0,0 +1,9 @@
+\documentclass[12pt]{article}
+
+\begin{document}
+
+$$
+  E = K_2 (\theta - \theta_0)^2 + K_3 (\theta - \theta_0)^3 + K_4 (\theta - \theta_0)^4
+$$
+
+\end{document}
diff --git a/doc/Eqs/dihedral_fourier.jpg b/doc/Eqs/dihedral_fourier.jpg
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diff --git a/doc/Eqs/dihedral_fourier.tex b/doc/Eqs/dihedral_fourier.tex
new file mode 100644
index 0000000000..960d3a8ea8
--- /dev/null
+++ b/doc/Eqs/dihedral_fourier.tex
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+\documentclass[12pt]{article}
+
+\begin{document}
+
+$$  
+  E = \sum_{i=1,m} K_i  [ 1.0 + \cos ( n_i \phi - d_i ) ]
+$$
+
+\end{document}
diff --git a/doc/Eqs/dihedral_nharmonic.jpg b/doc/Eqs/dihedral_nharmonic.jpg
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diff --git a/doc/Eqs/dihedral_nharmonic.tex b/doc/Eqs/dihedral_nharmonic.tex
new file mode 100644
index 0000000000..57a1d25284
--- /dev/null
+++ b/doc/Eqs/dihedral_nharmonic.tex
@@ -0,0 +1,9 @@
+\documentclass[12pt]{article}
+
+\begin{document}
+
+$$  
+  E = \sum_{n=1,n} A_n  \cos^{n-1}(\phi)
+$$
+
+\end{document}
diff --git a/doc/Eqs/dihedral_quadratic.jpg b/doc/Eqs/dihedral_quadratic.jpg
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diff --git a/doc/Eqs/dihedral_quadratic.tex b/doc/Eqs/dihedral_quadratic.tex
new file mode 100644
index 0000000000..049e4b2ec4
--- /dev/null
+++ b/doc/Eqs/dihedral_quadratic.tex
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+\documentclass[12pt]{article}
+
+\begin{document}
+
+$$
+  E = K (\phi - \phi_0)^2 
+$$
+
+\end{document}
diff --git a/doc/Eqs/improper_fourier.jpg b/doc/Eqs/improper_fourier.jpg
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diff --git a/doc/Eqs/improper_fourier.tex b/doc/Eqs/improper_fourier.tex
new file mode 100644
index 0000000000..47ac58ef01
--- /dev/null
+++ b/doc/Eqs/improper_fourier.tex
@@ -0,0 +1,9 @@
+\documentclass[12pt]{article}
+
+\begin{document}
+
+$$
+   E = K [C_0 + C_1 \cos ( \omega) + C_2 \cos( 2 \omega) ] 
+$$
+
+\end{document}
diff --git a/doc/Eqs/pair_tersoff.jpg b/doc/Eqs/pair_tersoff.jpg
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