I cannot find the equation for this graph.

[doubled5]

I need it for a program I am writing. I found it all over the net but never with an equation. After two days I'm giving up and hoping someone recognizes it. It doesn't have to be exact I can fix it up but the profile needs to be the same.

Here it is:

 

[symbolipoint]

That shape looks familiar, but not sure from what exactly. Physics or physical chemistry?

If you just want a function that fits the graph but you don't really know the mechanism making the shape, try polynomial function fit. Maybe third or fourth degree polynomial can give a good fit. Your graph shows fairly easily readable points. You'll only need the simplest of Linear Algebra skills to determine the function.

 

[doubled5]

Got it--Morse potential.

http://en.wikipedia.org/wiki/Morse_potential

f(x)=e^-2x+2-2e^-x+1

That shape looks familiar, but not sure from what exactly. Physics or physical chemistry?

Used to model nucleon-nucleon interactions.