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861.
Single crystals of sarcosine cadmium chloride were crystallised from a saturated aqueous solution containing stoichiomeric amounts of sarcosine and cadmium chloride, in 1:1 proportion. The intensity data were collected using a CAD-4 diffractometer with graphite monochromated MoKα, radiation. The crystal data are as follows: a = 6.916(1) Å, b = 13.855(3) Å, c = 7.981(1) Å, V = 764.1 Å · F.W. = 272.4, dexpt = 2.39 g · cm−3, dcalc = 2.368 g · cm−3, Z = 4 and the space group is P21/n. The structure has been solved to an R value of 0.023 for all the 1323 reflections with I > 2σ(I). The sarcosine molecule exists as zwitterion in the structure. The conformation of the sarcosine molecule is significantly changed due to the complexation of the molecule with cadmium chloride. The cadmium ion is found to have an octahedral coordination with both the oxygens of the carboxyl group of the amino acid and chlorines taking part in it. Since the complex has no water of hydration, only two hydrogen bonds of the types N H ‥ O and N H ‥ Cl are found. 相似文献
862.
Best conditions were established for the gel growth of three urinary crystals viz., calcium oxalate monohydrate, calcium hydrogen phosphate dihydrate and ammonium magnesium phosphate hexahydrate. The crystals grown were characterized using single crystal X-ray diffraction techniques and density measurements. Crystal growth experiments were carried out by incorporating the extracts or juices of some natural products in the gel media. By carefully observing the changes in the growth of crystals (compared to control experiments carried out at the same conditions), results about the inhibitory or promotery role of the substance incorporated were obtained. It was found that the extracts or juices of many of the naturally occurring substances have interesting inhibitory or promotery effects. These results may have useful applications in the treatment of recurrent stone patients. 相似文献