New structural effects in SrMoO4:Tm3+/Ho3+ crystals

• Published in: CrystEngComm Vol. 19; no. 2; pp. 295 - 33
• Main Authors: Kuz'micheva, G. M, Kaurova, I. A, Ivleva, L. I, Eistrikh-Geller, P. A, Rybakov, V. B, Khramov, E. V
• Format: Journal Article
• Language: English
• Published: 14.01.2017
• Subjects: Crystal defects; Crystal structure; Dopants; Doping; Interstitials; Molybdates; Rare earth metals; Single crystals
• ISSN: 1466-8033
• DOI: 10.1039/c6ce02155g

Rare-earth doping of strontium molybdate, SrMoO 4 , allows the combination of laser generation of light and its SRS conversion. The RE 3+ introduction into the Sr 2+ Mo 6+ O 4 matrix must inevitably lead to the appearance of point defects that will affect the possibility of the effective use of the material. In this work, we report comprehensive structural research of SrMoO 4 single crystals both nominally pure and doped with different Tm 3+ and Ho 3+ concentrations, undertaken for the first time, using X-ray single crystal and powder diffraction (crystal structure), EXAFS/XANES (local structure), and optical spectroscopy. The compositions of the grown crystals are established for the first time. Introduction of RE 3+ ions in the form of RE 3+ Nb 5+ O 4 leads to partial substitution of Mo 6+ ions by Nb 5+ along with the main location of Nb 5+ ions in the interstitial sites near the defect Mo 6+ sites with the formation of their own distorted tetrahedra. Dopant ions either replace partially the Sr 2+ ions (Ho 3+ ions) or are located in the interstitial sites near the defect Sr 2+ sites (Tm 3+ ions). The effective distribution coefficients of the dopants are determined. Ho 3+ and Tm 3+ doping of SrMoO 4 crystals leads to point defect formation in cationic and anionic sublattices.