Equation for the energy of an particle oscillator?

1. Dec 14, 2012

AATroop

So, my book claims that the effective spring stiffness of an atom (according to the Einstein model) is 2ks,i, but in an example problem they state one quantum of energy for an oscillator with an interatomic spring stiffness of 5N/m with 5 quanta is
$\hbar \times \sqrt(\frac{4(5)}{\mathrm{weight of atoms}})$

But, shouldn't it be

$\hbar \times \sqrt(\frac{\Huge{2}(5)}{\mathrm{weight of atoms}})$

If it's too difficult to understand, could someone just provide the standard equation involving planck's constant$/2\pi$ and the effective interatomic spring stiffness of an oscillator?

Last edited: Dec 14, 2012