Department of Physics, Presidency College, Chennai, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2012 Mar;88:77-81. doi: 10.1016/j.saa.2011.11.060. Epub 2011 Dec 19.
Synthesis and growth of a novel organic nonlinear optical (NLO) crystal of 4-aminopyridinium maleate (4APM) in larger size by the slow evaporation solution growth technique are reported. Single crystal and powder X-ray diffraction analyses reveal that 4APM crystallizes in monoclinic system with space group P2(1) with cell parameters a=8.140(4)Å, b=5.457(5)Å, c=10.926(10)Å and volume=481.4(7)Å(3). The grown crystal has been characterized by Fourier transform infrared and UV-visible spectral analyses. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) have been carried out to study its thermal properties. Dielectric measurements have been carried out to study the distribution of charges within the crystal. The mechanical strength of the crystal has been studied by using Vickers' microhardness test. The etching studies have been carried out on the grown crystal. The Kurtz and Perry powder SHG technique confirms the NLO property of the grown crystal and the SHG efficiency of 4APM was found to be 4.8 times greater than that of KDP crystal.
采用缓慢蒸发溶液生长技术合成并生长了一种新型有机非线性光学（NLO）晶体 4-氨基吡啶马来酸（4APM），尺寸较大。单晶和粉末 X 射线衍射分析表明，4APM 结晶于单斜晶系，空间群为 P2(1)，晶胞参数为 a=8.140(4)Å、b=5.457(5)Å、c=10.926(10)Å 和体积=481.4(7)Å(3)。所生长的晶体通过傅里叶变换红外和紫外-可见光谱分析进行了表征。进行了热重分析（TGA）和差热分析（DTA）以研究其热性能。进行了介电测量以研究晶体内部电荷的分布。通过维氏显微硬度试验研究了晶体的机械强度。对生长的晶体进行了蚀刻研究。库尔兹和佩里粉末 SHG 技术证实了生长晶体的 NLO 性质，并且发现 4APM 的 SHG 效率比 KDP 晶体高 4.8 倍。
