Ta có
\(\dfrac{{hc}}{{{\lambda _c}}} = {E_O} - {E_L}(1)\)
\(\dfrac{{hc}}{{{\lambda _t}}} = {E_P} - {E_L}(2)\)
Từ (1) và (2):
\(\begin{array}{l}{E_P} - {E_O} = \dfrac{{hc}}{{{\lambda _t}}} - \dfrac{{hc}}{{{\lambda _c}}}\\ = \dfrac{{6,{{625.10}^{ - 34}}{{.3.10}^8}}}{{0,{{412.10}^{ - 6}}}} - \dfrac{{6,{{625.10}^{ - 34}}{{.3.10}^8}}}{{0,{{434.10}^{ - 6}}}}\\ = 0,{2445.10^{ - 19}}J = 0,1528eV\end{array}\)