Spectroscopic properties of Sm3+ in KZnLa(PO4)2 in IR–VUV region

The KZnLa100%−xSmx(PO4)2 (x = 0.1, 1, 5, 10 at.%) compounds have been synthesized by a conventional solid-state method. The powder pattern of sample was indexed on the basis of a monoclinic cell, space group P121/A, with the lattice parameters: a = 6.839, b = 7.703, c = 6.511 Å, z = 4 and V = 254.3 Å3. The emission spectra recorded at low temperature are composed of transitions from the 4G5/2 multiplet to the 6H5/2 (17 566, 17 656, 17 858 cm−1), 6H7/2 (16 472, 16 540, 16 723, 16 770 cm−1), 6H9/2 (15 281, 15 320, 15 406, 15 531, 15 569 cm−1) and 6H11/2 (13 961, 13 995, 14 045, 14 114, 14 223, 14 259 cm−1). The spectroscopic properties were investigated in the range IR–VUV. It was found that the Sm3+ ions occupy position with one point symmetry site. The decay curves were pure exponential for 0.1–1 at.% of samarium and become non-exponential for higher Sm3+ concentrations. The Inokuti–Hirayama energy transfer process fit returns R0 = 10.96 Å, Cda = 4.04 × 10−52 m6 s−1 for S = 6. The electron–phonon coupling parameter α was found to be in the range 554–608 cm−1 for lines centred at 17 858, 16 770, 16 723 and 15 569 cm−1.

► The KZnLa(PO4)2 doped with Sm3+ compounds were synthesized up to our knowledge for the first time.
► The spectroscopic properties of these materials were done in the region form IR to VUV.
► The electron–phonon coupling strength was investigated.
► Influence of concentration and the temperature onto spectroscopic properties were investigated.