diff --git a/tools/lammps-gui/lammpsgui.cpp b/tools/lammps-gui/lammpsgui.cpp
index d2bf67a97b..68b29d4830 100644
--- a/tools/lammps-gui/lammpsgui.cpp
+++ b/tools/lammps-gui/lammpsgui.cpp
@@ -325,35 +325,35 @@ void LammpsGui::start_exe()
     QAction *act = qobject_cast<QAction *>(sender());
     if (act) {
         auto exe        = act->data().toString();
-        QString datacmd = "write_data ";
+        QString datacmd = "write_data '";
         QDir datadir(QDir::tempPath());
         QFile datafile(datadir.absoluteFilePath(current_file + ".data"));
-        datacmd += datafile.fileName();
+        datacmd += datafile.fileName() + "'";
         if (exe == "vmd") {
             QStringList args;
-            QFile vmdfile(datadir.absoluteFilePath(current_file + ".vmd"));
+            QFile vmdfile(datadir.absoluteFilePath("tmp-loader.vmd"));
             vmdfile.open(QIODevice::WriteOnly);
             vmdfile.write("package require topotools\n");
-            vmdfile.write("topo readlammpsdata ");
+            vmdfile.write("topo readlammpsdata {");
             vmdfile.write(datafile.fileName().toLocal8Bit());
-            vmdfile.write("\ntopo guessatom lammps data\n");
-            vmdfile.write("animate write psf ");
+            vmdfile.write("}\ntopo guessatom lammps data\n");
+            vmdfile.write("animate write psf {");
             vmdfile.write(datafile.fileName().toLocal8Bit());
-            vmdfile.write(".psf\nanimate write dcd ");
+            vmdfile.write(".psf}\nanimate write dcd {");
             vmdfile.write(datafile.fileName().toLocal8Bit());
-            vmdfile.write(".dcd\nmol delete top\nmol new ");
+            vmdfile.write(".dcd}\nmol delete top\nmol new {");
             vmdfile.write(datafile.fileName().toLocal8Bit());
-            vmdfile.write(".psf type psf waitfor all\nmol addfile ");
+            vmdfile.write(".psf} type psf waitfor all\nmol addfile {");
             vmdfile.write(datafile.fileName().toLocal8Bit());
-            vmdfile.write(".dcd type dcd waitfor all\nfile delete ");
+            vmdfile.write(".dcd} type dcd waitfor all\nfile delete {");
             vmdfile.write(datafile.fileName().toLocal8Bit());
-            vmdfile.write(" ");
+            vmdfile.write("} {");
             vmdfile.write(vmdfile.fileName().toLocal8Bit());
-            vmdfile.write(" ");
+            vmdfile.write("} {");
             vmdfile.write(datafile.fileName().toLocal8Bit());
-            vmdfile.write(".dcd ");
+            vmdfile.write(".dcd} {");
             vmdfile.write(datafile.fileName().toLocal8Bit());
-            vmdfile.write(".psf\n");
+            vmdfile.write(".psf}\n");
             vmdfile.close();
             args << "-e" << vmdfile.fileName();
             lammps.command(datacmd.toLocal8Bit());