# What happens if the electron density around a nucleus is decreased?

##### 1 Answer

**Electron density** is just the time-dependent probability of finding an electron somewhere. Wherever there is no electron density, no electrons can be observed. Hence, if you decrease electron density at a spot, you'll have a hard time finding an electron at that spot.

According to Electronic Structure Theory (first paragraph), **the electron is inextricably linked to the energy of a stationary atom**. Ever notice how every time you talk about energy states, relaxations, excitations, bond breaking/making, etc., you talk about the behavior of electrons? That's why.

The energy for the *helium atom* is approximately:

#E = K + V(r)#

#~~ 1/2m_(e1)v_(e1)^2 + 1/2m_(e2)v_(e2)^2 - e^2/(4piepsilon_0vecr_1) - e^2/(4piepsilon_0vecr_2) - (2e^2)/(4piepsilon_0vecr_"12")#

where

With less and less electrons observed around the nucleus, you simply get the convergence of the energy to

#color(blue)(lim_((K,V)->0) E) = cancel(1/2m_(e1)v_(e1)^2 + 1/2m_(e2)v_(e2)^2) - cancel(e^2/(4piepsilon_0vecr_1)) - cancel(e^2/(4piepsilon_0vecr_2)) - cancel((2e^2)/(4piepsilon_0vecr_"12"))#

#= color(blue)("0 J")#