diff --git a/NOTES.md b/NOTES.md
new file mode 100644
index 0000000..cf27b83
--- /dev/null
+++ b/NOTES.md
@@ -0,0 +1,22 @@
+Libraries:
+
+- https://github.com/widgetti/ipyvolume/tree/master/ipyvolume
+- https://github.com/nglviewer/nglview
+- https://github.com/nglviewer/ngl
+- https://github.com/cxhernandez/ipymol
+- https://github.com/3dmol/3Dmol.js
+- https://github.com/3dmol/3Dmol.js/tree/master/py3Dmol
+
+WebGL:
+
+- https://github.com/mrdoob/three.js/
+
+Typescript:
+
+- https://github.com/rmorshea/spectate
+
+Widgets:
+
+- https://ipywidgets.readthedocs.io/en/stable/examples/Widget%20Custom.html
+- https://ipywidgets.readthedocs.io/en/stable/examples/Widget%20Low%20Level.html
+
diff --git a/ipymolsysview/widget.py b/ipymolsysview/widget.py
index 0d31555..75addac 100644
--- a/ipymolsysview/widget.py
+++ b/ipymolsysview/widget.py
@@ -8,14 +8,13 @@
 TODO: Add module docstring
 """
 
+from ipymolsysview import pyunitwizard as puw
 from ipywidgets import DOMWidget
-from traitlets import Unicode
+from traitlets import Unicode, Int
 from ._frontend import module_name, module_version
 
-
 class Widget(DOMWidget):
-    """TODO: Add docstring here
-    """
+
     _model_name = Unicode('MolSysModel').tag(sync=True)
     _model_module = Unicode(module_name).tag(sync=True)
     _model_module_version = Unicode(module_version).tag(sync=True)
@@ -23,4 +22,21 @@ class Widget(DOMWidget):
     _view_module = Unicode(module_name).tag(sync=True)
     _view_module_version = Unicode(module_version).tag(sync=True)
 
-    value = Unicode('Hello IPyMolSysView!').tag(sync=True)
+    n_atoms = Int(0).tag(sync=True)
+
+    def __init__(self, molecular_system, selection='all', structure_indices='all', syntax='MolSysMT'):
+
+        .self.molecular_system = molecular_system
+        .self.selection = selection
+        .self.syntax = syntax
+        .self.structure_indices = structure_indices
+
+        from molsysmt import get
+
+        coordinates = get(self.molecular_system, selection=self.selection,
+                structure_indices=self.structure_indices, syntax=self.syntax)
+
+        coordinates_value = puw.get_value(coordinates, standard=True)
+        coordinates_value = coordinates_value[0]
+
+