5t2
5t2-
The theory shows that under certain pressure and Al concentration the 5E state will shift into the band gap from the bottom of conduction band . The 5E → 5T2 luminescence which can not be observed in normal condition will appear in such case .
理论证明了在一定的压力和Al成份下，~5E激发态将从导带底进入带隙，原在通常条件下观察不到的~5E→~5T2发光就能被观察到。