共查询到20条相似文献,搜索用时 281 毫秒
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P. Paufler 《Crystal Research and Technology》1995,30(7):920-920
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Vivek K. Gupta K. N. Goswami D. K. Gupta K. K. Bhutani 《Crystal Research and Technology》1995,30(3):359-366
The crystal structure of R(–)-1-tosyl-2-methylpyrrolidine has been determined by X-ray structure analysis. The compound crystallizes in the monoclinic space group P21 with cell parameters a = 7.858(1), b = 14.929(6), c = 11.128(1) Å, β = 105.42(1)°. The structure has been solved by direct methods and refined to R = 0.046. There are two crystallographically independent molecules A and B in the asymmetric unit. The pyrrolidine ring of molecule A is disordered with atom C4 occupying two possible sites. The S atom has a distorted tetrahedral coordination in both the molecules. Two bifurcated hydrogen bonds are observed. Molecules are held together by hydrogen bonds. 相似文献
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K. Jagannathan S. Kalainathan T. Gnanasekaran N. Vijayan G. Bhagavannarayana 《Crystal Research and Technology》2007,42(5):483-487
The organic material 4‐Ethoxybenzaldehyde‐N‐methyl 4‐Stilbazolium Tosylate (EBST) is a new NLO material and new derivative in Stilbazolium Tosylate family. In this work we synthesized the EBST, the derivative of DAST. By slow evaporation method, we have grown the EBST crystal. Powder XRD confirms the crystalline property, the lattice parameters are calculated from single crystal XRD data and the molecular structure also revealed. The crystal system is found as monoclinic. The crystalline perfection is assessed by the high‐resolution X‐ray diffractometry. A single and reasonably sharp peak observed in the diffraction curve indicates that the quality of the crystal is quite good without having any internal structural grain boundaries. The FTIR and proton NMR study confirm the presence of functional groups. From the UV – Vis Far IR absorption spectra the good transparency is revealed. The Kurtz Perry SHG test confirms the NLO property of the EBST crystal grown and it is 11 times greater than urea. The melting point of the grown crystal is found to be 237°C from the DSC curve. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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P. Rdolph 《Crystal Research and Technology》1992,27(6):824-824
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The phase equilibrium in the systems Na2SeO4–CuSeO4–H2O and Na2SeO4–ZnSeO4–H2O were studied and it was established that new phases were obtained – double salts with a composition: Na2Cu(SeO4)2 · 2 H2O and Na2Zn(SeO4)2 · 2 H2O. The fields of phase equilibrium of the double salts in the triple systems were determined. The composition of the new phases was investigated by the Schreinemackers' method of physico-chemical analysis, and the number of the water molecules of crystallization – by thermogravimetrical analysis. An X-ray diffraction analysis of the new phases obtained was done. 相似文献
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A. Andreeff 《Crystal Research and Technology》1991,26(4):446-446
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