diff --git a/data/dem/collision.in b/data/dem/collision.in
index 0dedb0a..9943fff 100644
--- a/data/dem/collision.in
+++ b/data/dem/collision.in
@@ -1,3 +1,3 @@
-2
+2 0 1 0 1 0 1
 1 0.1 0.166 0.55 0 1 0 0
 1 0.1 0.833 0.45 0 -1 0 0
diff --git a/lammps/atom.c b/lammps/atom.c
index 60de5df..bd8d871 100644
--- a/lammps/atom.c
+++ b/lammps/atom.c
@@ -450,6 +450,12 @@ int readAtom_in(Atom* atom, Parameter* param) {
 
     fgets(line, MAXLINE, fp);
     natoms = atoi(strtok(line, " "));
+    param->xlo = atof(strtok(NULL, " "));
+    param->xhi = atof(strtok(NULL, " "));
+    param->ylo = atof(strtok(NULL, " "));
+    param->yhi = atof(strtok(NULL, " "));
+    param->zlo = atof(strtok(NULL, " "));
+    param->zhi = atof(strtok(NULL, " "));
     atom->Natoms = natoms;
     atom->Nlocal = natoms;
     atom->ntypes = 1;