Growth of complex organic molecules unidirectional crystals from solution and their characterization

Abstract

In the recent years the technology and science of crystal growth newlinehave advanced rapidly for the development of new nonlinear optical newlinematerials The desire to utilize the properties of these materials in applications newlinesuch as telecommunications optical data storage and optical information newlineprocessing has created need for new materials with large second order newlinesusceptibilities As crystals have been playing a vital role in almost all newlinebranches of industry and daily life the importance of crystal growth for the newlineadvancement can be realized from the fact that crystals are used in electronic newlinedevices manufactured by electronic industries newlineThe present thesis gives a brief introduction to crystal growth newlinemethods instrumentation details of the characterization techniques and the newlinetheory of nonlinear optics NLO with the focus on second order nonlinearity newlineThe growth aspects of LSerine methyl ester hydrochloride LSMEHCl newlineLTyrosine methyl ester hydrochloride LTYMEHCl DPhenylglycinium newlinebromide DPGB and Ethyl triphenylphosphonium bromide dihydrate ETPB newlineand Methyl 2amino5bromobenzoate M2A5B single crystals were newlinediscussed In addition M2A5B single crystals were grown by novel newlineunidirectional SankaranayananRamasamy SR and the results were newlinecompared with conventional solution grown M2A5B crystals newlineThe LSerine methyl ester hydrochloride single crystals were newlinegrown by low temperature solution growth technique Single crystal Xray newlinediffraction studies revealed that the crystal belongs to monoclinic system with newlinespace group P2 From the UVVisible absorbance studies the newlineoptical band gap energy was calculated to be 5 eV The refractive indices of newlinethe crystal were determined using Brewster s angle method TGDTA and newlineDSC studies showed that the crystals were thermally stable up to 168 C newlineThe SHG efficiency of LSMEHCl was measured using KurtzPerry powder newlinetechnique and was found to be 116 times higher than that of KDP Particle newlinesize SHG dependency shows the existence of phase matching behaviour of newlineLSMEHCl newline newline