Determination of Trace Elements in the Single Crystal of Zinc Tungstate by AES

The determination of 6 trace elements (Mg, Ge, Cd, Si, Nb, Ce) in the single crystal sample of ZnWO₄ by AES is described. The sample is determined with WSP-1 emission spectrograph. The graphite powder, BaO and CaCO₃ are minxed in the ratio of 90: 5: 5, and used as buffer. Background was used as internal standards. The mixing ratio of the sample to the buffer was 2: 1 by weight. Carbon Cup electrocdes were filled by the sample mixture. A.C are was used as excitation source. The relative standard deviation is less than 14%. The recovery of this method is 95%~115%. The method has been applied to the determination of the single crystal sample in ZnWO₄ with satisfactory results.