Crystal Growth, Structure, and Properties of New Nonlinear Optical Materials: K2Ln(NO3)5·2H2O (Ln=La, Ce, Pr, Nd, Sm)

Single crystals of K2Ln(NO3)5·2H2O (Ln=La, Ce, Pr, Nd, Sm) (KLnN) were grown by evaporation in aqueous solution under constant temperature conditions. The structure of KPrN was determined from the single-crystal X-ray diffraction data. The KPrN crystallizes in the orthorhombic space group Fdd2 with parameters a=21.411(3) ?, b=11.2210(10) ?, c=12.208(2) ?, Z=6, V=2933.0(7) ?3, R=0.0240, Rw=0.0603. The powder second harmonic generation (SHG) intensities of KLnN (Ln=La, Ce, Pr, Nd, Sm) are also studied. The results demonstrate that their SHG intensities are 4–9 times larger than that of KDP, in which the KPrN shows the highest SHG coefficient.