It is an interesting topic to reveal the origin of the SHG intensity enhancement after substitution from alkali and alkali-earth metal atoms to cadmium in a series of apatite-like borates KSr4(BO3) 3, Ca5(BO3)3F, Cd 5(BO3)3F. Combined with the first-principles method, SHG-density method and real-space atom-cutting method, the electronic structure, the optical properties and the contribution of respective ion and ion groups have been investigated. Second harmonic generation (SHG) responses are mainly attributed to BO3 groups with π conjugated configuration and their alignment framework. The contributions of A site are more important in CaBOF and CdBOF compounds than in KSrBO. It is also demonstrated that the strong covalent interactions between the boron-oxygen groups and the cadmium atoms contribute the enhancement of SHG responses after substitution from alkali and alkali-earth metal atoms.
Xinjiang Tech Inst Phys & Chem CAS, Key Lab Funct Mat & Devices Special Environm CAS, Xinjiang Key Lab Elect Informat Mat & Devices, Urumqi 830011, Peoples R China;Univ Chinese Acad Sci, Beijing 100049, Peoples R China;Shihezi Univ, Sch Sci, Dept Phys, Shihezi 832000, Peoples R China;Xinjiang Inst Engn, Engn Dept Chem & Environm, Urumqi 830091, Peoples R China
Jing, Qun,Dong, Xiaoyu,Yang, Zhihua,et al. The interaction between cations and anionic groups inducing SHG enhancement in a series of apatite-like crystals: A first-principles study[J]. Journal of Solid State Chemistry,2014,219(11):138-142.