What Is the Role of Angle Potentials in Atomic Interactions?

[sqljunkey]

I have been trying to understand angle potentials such as described in this website, https://lammps.sandia.gov/doc/angle_style.html . Supposing two bonds have a certain angle they have to adhere to, what does this mean for that one atom being bound to, that only x amount of atoms can bind with it, that the atom being bound to has different potentials at different angles? Or is the angle potential just a mechanism/model to explain natural phenomena?

 

[DrClaude]

Energy is a function of the relative position of the atoms. Take water for example: the energy changes not only when a O-H bond changes length, but also when the relative angle between the two O-H bonds changes.