Crystal-field splitting of Ce^(3+)in narrow-band phosphor SrLiAl_(3)N_(4)

As a promising narrow-band phosphor,SrLiAl_(3)N_(4)has a seemingly ultra-small total crystal-field splitting of only 2400 cm^(-1)with Ce^(3+)as dopant ions.This paper is devoted to unravel this anomalous phenomenon based on semi-quantitative crystal-field calculations.The results show that there may exist undetected excitation peaks immersed in the host excitation band,and the calibrated crystal-field splitting is 27000 cm^(-1).comparable to those of other Ce^(3+)doped phosphors.In the end the effect of polyhedral deformation on energy level is briefly discussed.