“…The growth conditions of pure or RE 3+ -doped APb 2 X 5 (A=K,Rb ; X=Cl,Br) and Tl 3 PbX 5 (X=Cl,Br) single crystals for MIR laser and/or nonlinear optical applications have been exhaustively detailed in an impressive body of work [Amedzake et al, 2008;Atuchin et al, 2011;Bekenev et al, 2011;Condon et al, 2006b;Ferrier et al, 2006aFerrier et al, , 2006bGang et al, 2008;Isaenko et al, 2001;Nitsch et al, 1993Nitsch et al, , 1995aNitsch et al, , 1995bNitsch et al, , 2004Nitsch & Rodová 1999;Oyebola et al, 2010;Rodová et al, 1995;Roy et al, 2003;Singh et al, 2005;Tigréat et al, 2001;Velázquez et al, 2006aVelázquez et al, , 2006bVelázquez et al, , 2009Voda et al, 2004;Wang et al, 2007]. Special safety conditions for the manipulation of large amounts of TlCl or TlBr powders must be followed, but this does not entail insuperable difficulties [Peter & Viraraghavan, 2005].…”