Abstract In the present work, the organic nonlinear material 3-methyl 4-nitropyridine 1-oxide (POM) has been synthesized from 3- picoline-N-oxide. Single crystals of POM have been grown by solvent evaporation method. Crystals of dimensions 1.1×0.8×0.4 cm 3 have been obtained by this technique. FT-NMR and FTIR techniques have confirmed its molecular and structural identification. The grown crystals have been characterized by single crystal X-ray diffraction method and their lattice parameters were determined. Optical transmittance spectrum shows transmittance of 55%. To investigate the mechanical properties of POM crystals, Vickers hardness studies were carried out in different planes and the hardness values have been determined. Second harmonic generation was observed by using Q-switched Nd:YAG laser confirming the NLO property. Laser damage threshold value has been determined using Q-switched Nd:YAG laser operating at 1064 nm with 20 ns pulses.

中文翻译：

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3-甲基 4-硝基吡啶 1-氧化物 (POM) 单晶的合成、晶体生长和表征

摘要 在目前的工作中，有机非线性材料 3-甲基 4-硝基吡啶 1-氧化物 (POM) 已由 3-甲基吡啶-N-氧化物合成。POM 单晶已通过溶剂蒸发法生长。通过该技术已获得尺寸为1.1×0.8×0.4 cm 3 的晶体。FT-NMR和FTIR技术已证实其分子和结构鉴定。生长的晶体已经通过单晶X射线衍射法表征并确定了它们的晶格参数。光学透射光谱显示透射率为55%。为了研究 POM 晶体的机械性能，在不同平面上进行了维氏硬度研究，并确定了硬度值。通过使用 Q 开关 Nd:YAG 激光观察到二次谐波的产生，证实了 NLO 特性。