5I7 → 5I8 infrared luminescence spectrum of Cs2NaHoCl6

Abstract

The 300-15 K luminescence spectrum of Cs2NaHoCl6 is reported for the spectral region 4550–5300 cm−1. In agreement with the calculated magnetic dipole (MD) intensity ratios, twenty MD allowed pure electronic transitions are observed and assigned, corresponding to transitions between the crystal field components of 5I7 → 5I8. The ungerade vibronic origins associated with these transitions are at least an order of magnitude weaker. All of the crystal field levels of the 5I7, 5I8 Russell—Saunders terms are assigned from the spectral analysis. The long-term lifetime of the 5I7 levels is near 50 ms at 85 K.