The Microstructure and Chemical Bonds of β-C_2S Under the High Energy Ball Grinding Function

Using the laser granularity survey technology , logy, X-ray powder diffraction, scanning electron microscopy （SEM） and infrared spectrum anal）sis methods, we studied the microscopic structure and chemical bonds changes of β-C2 S monomineral under the high energy ball grinding function. The result indicates that, continuously under the mechanical power, β-C2 S crystal size would decrease, the micro strain and the effective Beff parameter would increase, and the amorphous phases would be presented. Furthermore, the mechanical power would cause Si-O bond broken and reorganized, the specific surface area would increase, the energy of micro-powder agglomeration vibration would be enhanced and the crystal would be disordered. Finally, β- C2 S was caused to have the mechanochemical change and the activity enhancement.

Accurate design and synthesis of nonlinear optical crystals employing KBe_(2)BO_(3)F_(2) as structural template

In spite of decades of great efforts,it is still very challenging to realize accurate design and synthesis of second-order nonlinear optical(NLO)crystals.KBe_(2)BO_(3)F_(2)(KBBF)is the sole NLO material that can output deep-ultraviolet light by direct second-harmonic generation process,so it is an ideal choice to use KBBF as the structural template to design environment-friendly candidates with better growth habit based on the reported compounds.In this review,we will elaborate the accurate design and synthesis of high-performance NLO ma-terials from the perspective of microscopic crystal structure based on KBBF,hoping to provide deep understanding on how to rationally design and synthesize targeted compounds efficiently and quickly.In addition,according to multiple requirements on ultraviolet NLO crystals,including second-harmonic generation,cut-off edge,and birefringence,we propose a new concept so-called quality factor to comprehensively evaluate the overall per-formance of new ultraviolet NLO materials.This concept would help to directly and readily evaluate the ability of an ultraviolet NLO material to achieve practical NLO output.