From fb705efa84eb862d01842c3dd4fef8d733a66e84 Mon Sep 17 00:00:00 2001
From: athomps <athomps@f3b2605a-c512-4ea7-a41b-209d697bcdaa>
Date: Wed, 24 Sep 2014 00:46:11 +0000
Subject: [PATCH] Change fix box/relax example to be more efficient

git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@12532 f3b2605a-c512-4ea7-a41b-209d697bcdaa
---
 examples/min/in.min.box | 45 +++++++++++++++++++++++++++++++++++------
 1 file changed, 39 insertions(+), 6 deletions(-)

diff --git a/examples/min/in.min.box b/examples/min/in.min.box
index 6326221728..222fe8f9ba 100644
--- a/examples/min/in.min.box
+++ b/examples/min/in.min.box
@@ -1,5 +1,6 @@
-# 2d Lennard-Jones melt and subsequent energy minimization
-
+# 2d Lennard-Jones melt and subsequent energy minimization,
+# followed by box relaxation to a target stress state
+#
 units		lj
 dimension	2
 atom_style	atomic
@@ -36,15 +37,47 @@ thermo		100
 
 run		1000
 
+# perform the box relaxation by progressively
+# adding more degrees of freedom, for smoother
+# convergence
+
 neigh_modify	delay 0 every 1 check yes
 
 velocity	all create 0.0 1
 thermo		50
+
+# atoms only
+
 minimize	1.0e-6 0.001 1000 10000
 
-fix             3 all box/relax x 1.0 y 2.0 vmax 1.0e-4 nreset 100
+# isotropic volume relaxation to hydrostatic target
+
+fix             3 all box/relax iso 1.5 vmax 1.0e-3
+
+variable        emin equal pe+f_3/atoms
+thermo_style    custom step temp pe pxx pyy pxy f_3 v_emin
+
+# anisotropic volume relaxation to hydrostatic target
+
+minimize	0.0 10.0e0 10000 100000
+
+fix             3 all box/relax aniso 1.5 vmax 1.0e-3
+
+minimize	0.0 10.0 10000 100000
+
+# anisotropic volume relaxation to non-hydrostatic target
+
+fix             3 all box/relax x 1.0 y 2.0 vmax 1.0e-3
+
+minimize	0.0 10.0 10000 100000
+
+minimize	0.0 1.0 10000 100000
+
+minimize	0.0 1.0e-2 10000 100000
+
+# Final refinement uses nreset to eliminate stress offset
+
+fix             3 all box/relax x 1.0 y 2.0 vmax 1.0e-3 nreset 100
 
-thermo_style    custom step temp pe pxx pyy pxy
+minimize	0.0 1.0e-4 10000 100000
 
-min_modify      line quadratic
-minimize	0.0 1.0e-6 10000 100000
-- 
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