Thiourea-doped ammonium dihydrogen phosphate: A single crystal neutron diffraction investigation

Pramana

M R Suresh Kumar¹  A Jayarama¹  R Chitra2²  R R Choudhury²  S M Dharmaprakash¹ 

[1] Department of Physics, Mangalore University, Mangalagangotri 574 199, India$$;Solid State Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India$$

关键词: Ammonium dihydrogen phosphate;    neutron diffraction;    single crystal;    ferro-electric.;   

DOI  :  

学科分类：物理（综合）

来源: Indian Academy of Sciences

【 摘 要 】

Thiourea-doped ammonium dihydrogen phosphate (TADP) exhibits nonlinear optical property and the second harmonic generation efficiency of these crystals is three times that of pure ammonium dihydrogen phosphate (ADP) crystal. In this context, the study of structural distortion in the thiourea-doped ADP crystal is significant, hence single neutron diffraction investigations were undertaken. The final 𝑅-factors are: 𝑅[𝐹2 > 2𝜎(𝐹2)] = 0.11, Goodness of fit (𝑆) = 1.15. Though the dopant could not be located from the difference Fourier map, the cell parameters (𝑎 = 𝑏 = 7.531(3) Å, 𝑐 = 7.544(5) Å) were found to be significantly greater than that of pure ADP at RT (𝑎 = 𝑏 = 7.502(1)$ ̊Å, 𝑐 = 7.546(1) Å). This indicates that the dopant concentration in the crystals is small but enough to bring changes in the overall average structure.

【 授权许可】

Unknown