Development of high-quality and large-size 2-amino 4,6-dimethyl pyrimidine 4-nitrophenol single crystal by immersed Sankaranarayanan–Ramasamy (ISR) method

The optically good quality organic 2-amino 4,6-dimethyl pyrimidine 4-nitrophenol (AMP4N) single crystal (length 120 mm and diameter 15 mm) was grown by immersed Sankaranarayanan–Ramasamy (ISR) method at ambient temperature using methanol as solvent. The ampoule was specially designed for the growth of good quality and bulk size unidirectional single crystal by slow cooling condition. The unwanted temperature gradient developed on the solution surface was completely avoided, hence the formation of secondary nucleation on top of the ampoule is avoided. The growth apparatus and optimization parameters have been made simpler compared to the conventional SR method. Growth direction parallel to the gravity direction can be easily achieved, hence slanted growth could be avoided within the ampoule and also linear transportation of embryos from solution to crystal–solution interface is achieved. The ISR method-grown single crystal was subjected to various characterizations. The structure of AMP4N was confirmed by single-crystal X-ray diffraction analysis. The optical behaviour of the grown crystal was analysed by UV–visible NIR spectrophotometer. Fourier transform infrared spectrum is used to confirm the functional groups present in the AMP4N crystal. The negative photoconductivity nature of the AMP4N single crystal was determined by photoconductivity analysis. The piezoelectric (d 33 ) coefficient has been measured, and the d 33 value shows that it is a suitable material for piezoelectric devices. The full-width at half maximum (FWHM) values of various regions indicate that the entire grown crystal has high crystalline perfection and is optically homogeneous. Birefringence interferometry shows that the grown crystal has good refractive index homogeneity. The novel crystal growth ISR method has been reported, and also various studies reveal that the ISR method-grown crystals are favourable for high performance optical device applications.