3 – D Helium Molecule
Tutorial
Alice Project
Duke University
Professor Susan H. Rodger
Gaetjens Lezin
June 2008
Intro Set Up
• We will be building a 3 – D electron cloud
model of a helium atom
• We will also add a billboard that will serve as a
legend. Use paint or your favorite drawing
tool to do this step.
• To begin open a new Alice world and choose
the sand template.
Building the nucleus
• Click the green add
objects button
• Select the local
directory and scroll over
to the shapes folder
• Select the object
SphereHighPoly, add
four of these objects
into your world
Hint: If you cannot find the
SphereHighPoly Object, click search
gallery and type “SphereHighPoly”
Your World should look like this
Notice the four new items on
the object tree
Click and
hold on the
shape to
drag it
• Now line them up in a row by clicking on them and
moving them left or right
• They should be touching and half way sunk into
the ground
• The next slide will show you what they should look
like when they are in a line.
Name the shapes and set their color
• Look at the object tree and right
click on the SpereHighPoly object
and select rename
• Name it ProtonA
Four shapes in a line
• Now select the properties tab
click next to color and change it
to red
• The next slide will show you how
your progress should look
• Your spheres may be in a
different order. That is fine.
Cont…
• We want to name and set the
second shape, (SphereHighPoly2),
the same way we did the first one
• To do this, right click on
SphereHighPoly2, then rename it
NeutronA
• Last step, click the properties tab
and set the color to yellow
Right click and
rename to NeutronA
Click next to color
then select Yellow
1 shape
named and
colored
How it should look for now
Cont..
• We are going to repeat the
instructions on the last slide for
the third shape we added,
(SphereHighPoly3)
• rename this object ProtonB
• Set its color to red
Cont…
• Now repeat the
same steps for
the last sphere
in the object
tree
• Rename it
NeutronB
• Set its color to
Yellow
Resize the nucleus atoms
• There are a few ways to
resize items in Alice
• We will use methods,
this will reduce
ambiguity
• Right click on ProtonA
• Click on Methods
• Select resize
• Select other and type
.5 then click Okay
Resizing cont…..
• We want to make all the
protons and neutrons
the same size
• So repeat the resize
instructions on the last
slide for NeutronA,
ProtonB and NeutronB
• The next step is
positioning the atoms
All the nucleus atoms resized to .5 units
Positioning the Nucleus atoms
• Lets start off with the leftmost atom, this should be
ProtonB
• If it is not, re – order your line so you have in order
from left to right
– ProtonB, NeutronA, ProtonA, NeutronB
• Once the atoms have been resized it is easy to
rearrange the order
• Just click an object hold and drag it to where you
want it
Hint: Click on an object and its name will be highlighted in the
object tree
Positioning cont…
• Once you have them lined
up we will move them
• right click on ProtonB and
select Methods
• Select Move, then Up
• Choose Other, type 2 and
click Okay
This is what it should
look like after you move
ProtonB up 2 meters
Positioning cont…
• Now lets move the right
most atom, (NeutronB),
up 2 meters
• Follow the same
instructions from the
last slide
NeutronB has moved up 2
meters
• Next step is to
put the 4 atoms
together
• We will use
methods to
adjust their
positions
Cont…
• Right click on
NeutronB and
select methods
• Then select move
toward
• Select 2 meters,
then select
ProtonB
The atoms should look like this
after the instruction
Cont…
• Now we will move
NeutronA up 1 meter
• Click on NeutronA
then select methods
• Click Move, then Up
• Select other from the
dropdown menu
• Enter 1.5 then click
Okay
• If they are not
touching click on it
and move it until they
are touching
After you move
NeutronA up 1.5
meters your
world should
look like this
Cont…
• Now we need to move the last
atom,(ProtonA ), up
• Click on ProtonA and select methods,
then move
• Select up, then select 1.5
Next we want to move ProtonA towards
NeutronA a distance of ½ meter
ProtonA moved up 1.5 meters
I will show you how to do this on the next slide
if you don’t remember how
Cont….
• Right Click on
ProtonA then
choose
methods
• Select move
toward
• Choose ½
meter, then
Neutron A
Your world should look like this
after you run the previous
instruction
Note: If they are not touching
click on it and move it so they
are touching like the picture
shows
cont
• The last atom we
need to position is
ProtonB
• Right click on
ProtonB and choose
Move Toward
• Select 3/4 meter
then choose
Neutron B
Move
Objects
freely
with
this
tool
The world looks like this after
ProtonB is moved
It is not exactly in a perfect
position
Use the “move objects freely
tool”(the cursor ) to get it
exactly right
Creating the Electron
Cloud
• Add another
sphereHighPoly object
to your world
• It is located under Local
Directory, then shapes.
You should already be
here
• If you cant find it search
for “sphereHighPoly”
Resize the electron Cloud
• Click on the object you just added
and resize it by 2
• Then use its move method to
move it up 2 meters
• Now change the opacity to 30%
• Click on the properties tab, then
click next to opacity and select
30%
Once you set
the opacity
the electron
cloud looks
like this
We need to
position the
electron cloud
so the nucleus
is in the
middle
Position the Electron Cloud
• Select the up and down
tool and move the
electron cloud down a
little by clicking on it and
holding it
Cont…
• Now select the “move
objects freely” tool to
move the electron
cloud a little to the left
Your finished product should
look something like this
Click , hold and
drag the Electron
cloud a little to
the left
Set up some properties
• With the electron cloud
in place, we want to set
all the atoms inside the
nucleus a vehicle to the
electron cloud
• Before we do this, lets
name the object
“SphereHighPoly” in the
object tree to
“ElectronCloud”
Right click on a
item on the
object tree then
select rename to
change its name
Your object tree should look like this
at this point
Setting properties cont…
• Click on ProtonA on the
object tree
• In the Properties tab click
next to vehicle and select
ElectronCloud
• Repeat this step for
– NeutronA
– ProtonB
– NeutronB
Create the electrons
• We will add 2 electrons to the
world. First Navigate to shapes
in the local gallery
• Click on SphereHighPoly and
add it to the world, just like
you have done before
• Right click on it in the world,
select methods, resize, choose
other and type .5
• On the properties tab, click
next to color and select green
Your world should look like this
once you have set the size and
color of the electron
Name Electron1
• Now lets give a name
to our electron
• Like you have done
before go to the object
tree and right click on
SphereHighPoly and
rename it Electron1
Your object tree
should look like this
once you have run
the instruction
Position Electron1
• Eventually we will make the electrons
revolve around the electrons cloud
• For this to work right we have to position
the electrons in the proper place
• I will try and use methods to position the
electron but you can also use the Move
Objects Freely Tool
Click Add Object to get
these options
Positioning Electron1 with Methods
• Right click Electron1
on the object tree and
select Move, then up,
then other
• Type 4 meters and
click Okay
The world should look like this
once you have moved electron1 up
4 meters
Hint: Click and
move electron1 to
resemble the
picture
Create electron 2
•
•
•
•
•
Go back into add objects then to local gallery
Go into the shapes folder and add another sphereHighPoly object
Change the color to green
Resize it to .5 meter
And rename it Electron2
More Properties
• We want to set the vehicle
properties of Electron1 and
Electron2 to the Electron Cloud
• So click on Electron1 on the
object tree
• In the details panel click on the
properties tab and click next to
vehicle
• From the drop down menu select
ElectronCloud
• Repeat all of the previous steps
on this slide for Electron2
Position the Model
• Now all the properties are setup
• We just need to position the
entire model so that it is in the
middle of out screen
• To do this use the “move Object
freely tool”
• Click on the ElectronCloud in the
world window and move it
backwards
• Next click on the “up and down
tool” and move it up a little bit
• Notice all the sub atomic particles
move with the electron cloud
Your world should look like this
after your are done moving the
model backwards with the Move
objects freely tool and up with the
up and down tool
Prepare to Code
• Click Done to go back to the initial Alice
window
• Next we will code the model so that the
electrons revolve around the Electron
cloud together
Begin Coding
• First click on the world
tab on the object tree
• In the details panel click
on Create a new variable
• A window will pop up
• Type Electrons in the
name box
• Click the radio button
next to Objects
• Click the check box that
says make a list
• Add two new items to the
list
Coding continued….
• Click next to none and
select Electron1
• Click next to the second
none and choose
Electron2
• Then click OK
Cont..
• Now drag a for all
together statement into
the editor window
• From the drop down
menu select expressions
then World. Electrons
• Then click on Electron1
on the Object Tree
• Then click on methods in
the details panel
Cont…
• Scroll down to the
statement that says
turn at speed
• Drag and drop this into
the for all together
statement
• From the drop down
menu select forward
• then .25 revolutions per
second
Cont…
• Now lets drag the tab that
says item_from_Electrons
• Drop it over Electron1 in
the For all together
statement
• Then click the triangle
facing down next to more
• Select asSeenBy
• Then ElectronCloud
Cont…
• Click the triangle next to
more again and select
duration
• Choose other
• Put in a large number
like 1,000,000,000
• Click Okay
Hint: Press play, You may need to reposition
the electrons if they don’t revolve properly
Finishing Touches
• You may want to move
Electron2 a little further
away from the
ElectronCloud. Simply use
the move objects freely tool
to do this
• Also you may want to add a
billboard that is a legend of
what each piece of your
model represents for
example I used paint to
create this legend
• Save the Picture as any one
of the following;
JPEG,PNG,BITMAP,GIF
• Alice will accept all of these
formats
Cont…
• To add this billboard to my world
I will click on file then choose
Make a Billboard
• Then go to the folder where the
picture I created using paint is
located then hit Enter
Note: Place the billboard where you want
it.
A Finished Picture
I hope you enjoyed my tutorial
Have fun with Alice!!
:-D