Neodymium and chromium segregation at high-temperature crystallization of (Nd,Y)Al3(BO3)4 and (Nd,Y)Ca4O(BO3)3 doped with Cr3+

Pure and chromium-doped (Nd,Y)Al-3(BO3)(4) (NYAB) single crystals weighting up to 13 g each and (Nd,Y)Ca4O-(BO3)(3) (NYCOB) with typical weight 250 g have been grown from fluxed melts based on potassium trimolibdate and by Czochralski technique, respectively. Chemical composition of the crystals grown was determined by microprobe analysis. The neodymium content in NYAB and NYCOB is less than its concentration in the borate of initial melt or fluxed melt. The main chromium amount incorporates in NYAB at early stages of crystal growth process and extremely exceeds its value in the dissolved borate of liquid phase. The Y3+-and Nd3+-sites in NYCOB structure are not suitable for chromium. (C) 2002 Elsevier Science B.V. All rights reserved.