title: Deep-ultraviolet nonlinear optical crystals: Ba3P3O10X (X = Cl, Br).
abstract: Deep-ultraviolet nonlinear optical (deep-UV NLO) crystals are of worldwide interest for the generation of coherent light with wavelength below 200 nm by the direct second-harmonic generation (SHG) output from solid-state lasers. The unprecedented deep-UV NLO phosphates representing their own structure types, Ba3P3O10Cl (BPOC), Ba3P3O10Br (BPOB), have been discovered, which display moderate powder SHG intensities in type I phase matchable behaviors with a short UV cutoff edge of 180 nm (measured by a single crystal, one of the shortest values among phosphates to date). Insightfully, the geometry and polarization of the C1-P3O10(5-) building unit are affected by the crystal packing. DFT calculations and cutoff energy dependent SHG coefficient analyses reveal that the SHG origin is from the cooperation of asymmetric C1-P3O10(5-) anion, Ba(2+) cation, and Cl(-)/Br(-) anion.
authors.affiliation: Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , Fuzhou, Fujian 350002, People's Republic of China.
authors.forename: Peng
authors.initials: P
authors.lastname: Yu
authors.forename: Li-Ming
authors.initials: LM
authors.lastname: Wu
authors.forename: Liu-Jiang
authors.initials: LJ
authors.lastname: Zhou
authors.forename: Ling
authors.initials: L
authors.lastname: Chen