来源：ACS Publications
We present a detailed structural investigation of a series of seven new quaternary Li-containing selenosilicates, RE3LiSiSe7 (RE = La–Nd, Sm, Gd, and Tb), prepared using the boron chalcogen mixture (BCM) method in the presence of LiCl flux. Single crystals of high quality were grown, and single-crystal X-ray diffraction was utilized to determine their structures. The compounds RE3LiSiSe7 (RE = La–Nd, Sm, Gd, and Tb) crystallize in hexagonal P63 space group. In the structure, the three-dimensional framework is built from RESe8 bicapped trigonal prisms, SiSe4 tetrahedra, and LiSe6 octahedra. Bulk polycrystalline samples were synthesized for magnetic susceptibility, UV–vis diffuse reflectance, and second-harmonic generation (SHG) measurements. Magnetic property measurements revealed paramagnetic behavior of RE3LiSiSe7 (RE = Ce and Nd). RE3LiSiSe7 (RE = La) exhibits a wide band gap (∼2.4(1) eV) and strong infrared second-harmonic generation (SHG) efficiency, approximately ∼1.3 × AgGaS2 at 2090 nm, but is nonphase-matchable at that wavelength.