# Why are there no electronic transitions in "He"^(2+)?

Jul 9, 2017

Well, because it has no electrons... And hence there can be no electronic transitions to speak of. But ${\text{He}}^{+}$ is another story. Why?

The Bohr model of course cannot apply... its very definition models the atom as a positively-charged nucleus surrounded by electrons that travel in circular, fixed orbits (that violate the Heisenberg Uncertainty Principle).

At least hydrogen atom has one electron. But ${\text{He}}^{2 +}$ has none. Zero.

$\text{He} : 1 {s}^{2}$

$\implies {\text{He}}^{2 +} : 1 {s}^{0}$

Why does the Bohr model apply to ${\text{He}}^{+}$?