Eh... the electron is attracted equally in different directions should imply that it's in an unstable equilibrium (you can't have stable equilibria in electrostatics other than colocated with an opposite charge). There must be something more interesting going on.
No, I mean that an electrostatic potential cannot have local minima other than in locations of opposite charges. Thus, something more interesting must be going on there, probably involving energy level quantization.
You might wish to be aware of thermoluminescent dosimetry _and_ optically stimulated luminescence.
@robryk Exactly - unstable equilibrium, but *locally* stable. There's a lower energy configuration "just over the hill", and when you give it that, via heat*, it pops over.
*(Or, I'd be interested to see, UV light or similar, cos the same thing happens with toughened glass.)