git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@12419 f3b2605a-c512-4ea7-a41b-209d697bcdaa

examples/README

@@ -92,6 +92,7 @@ prd:      parallel replica dynamics of vacancy diffusion in bulk Si
 reax:     RDX and TATB models using the ReaxFF
 rigid:    rigid bodies modeled as independent or coupled
 shear:    sideways shear applied to 2d solid, with and without a void
+snap:     use of SNAP potential for Ta
 srd:      stochastic rotation dynamics (SRD) particles as solvent
 tad:      temperature-accelerated dynamics of vacancy diffusion in bulk Si
 voronoi:  test of Voronoi tesselation in compute voronoi/atom

examples/snap/Ta06A.snapcoeff

@@ -0,0 +1,36 @@
+
+# LAMMPS SNAP coefficients for Ta_Cand06A
+
+1 31
+Ta 0.5 1
+-2.92477
+-0.01137
+-0.00775
+-0.04907
+-0.15047
+0.09157
+0.05590
+0.05785
+-0.11615
+-0.17122
+-0.10583
+0.03941
+-0.11284
+0.03939
+-0.07331
+-0.06582
+-0.09341
+-0.10587
+-0.15497
+0.04820
+0.00205
+0.00060
+-0.04898
+-0.05084
+-0.03371
+-0.01441
+-0.01501
+-0.00599
+-0.06373
+0.03965
+0.01072

examples/snap/Ta06A.snapparam

@@ -0,0 +1,12 @@
+# LAMMPS SNAP parameters for Ta_Cand06A
+
+# required
+rcutfac 4.67637
+twojmax 6
+
+# optional
+
+gamma 1
+rfac0 0.99363
+rmin0 0
+diagonalstyle 3

examples/snap/Ta06A_pot.snap

@@ -0,0 +1,16 @@
+# Definition of SNAP potential Ta_Cand06A
+# Assumes 1 LAMMPS atom type
+ 
+variable zblcutinner equal 4
+variable zblcutouter equal 4.8
+variable zblz equal 73
+
+# Specify hybrid with SNAP, ZBL
+
+pair_style hybrid/overlay &
+zbl ${zblcutinner} ${zblcutouter} &
+snap
+pair_coeff * * zbl 0.0 # Needed to activate hybrid cross-types
+pair_coeff 1 1 zbl ${zblz}
+pair_coeff * * snap Ta06A.snapcoeff Ta Ta06A.snapparam Ta
+

examples/snap/in.snap

@@ -0,0 +1,45 @@
+# Demonstrate SNAP Ta potential
+
+# Initialize simulation
+
+variable nsteps index 100
+variable nrep equal 4
+variable a equal 3.316
+units		metal
+
+# generate the box and atom positions using a BCC lattice
+
+variable nx equal ${nrep}
+variable ny equal ${nrep}
+variable nz equal ${nrep}
+
+boundary	p p p
+
+lattice         bcc $a
+region		box block 0 ${nx} 0 ${ny} 0 ${nz}
+create_box	1 box
+create_atoms	1 box
+
+mass 1 180.88
+
+# choose potential
+
+include Ta06A_pot.snap
+
+# Setup output
+
+thermo		10
+thermo_modify norm yes
+
+# Set up NVE run
+
+timestep 0.5e-3
+neighbor 1.0 bin
+neigh_modify once no every 1 delay 0 check yes
+
+# Run MD
+
+velocity all create 300.0 4928459
+fix 1 all nve
+run             ${nsteps}
+