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Studies On The Growth And Characteristics Of Structural And Photoconductivity Of Bis Glycine Maleate Single Crystal  [PDF]
V. J. Priyadharshini And G. Meenakshi
Golden Research Thoughts , 2013, DOI: 10.9780/22315063
Abstract: A single crystal of Bis glycine maleate has been grown from aqueous solution by slow evaporationmethod by optimizing the growth parameters within a period of 45 days. From the x-ray diffraction the crystal wasfound to be crystallize in hexagonal structure with a=7.402 , b=7.04 , c= 5.48 and á=a=90°, =120°. Thefunctional group was confirmed in FTIR analysis. The UV-Vis spectral analysis has revealed the absence of highabsorption region between 200 to 800nm. The optical band gap was calculated and found to be 4.06 eV. Thephotoconductivity study confirmed that it is a positive photoconductivity
Crystal growth and structure of L-methionine L-methioninium hydrogen maleate—a new NLO material
Subramanian Natarajan et al
Science and Technology of Advanced Materials , 2008,
Abstract: A new organic nonlinear optical (NLO) crystal from the amino acid family, viz., L-methionine L-methioninium hydrogen maleate (LMMM), has been grown by slow evaporation method from aqueous solution. Bulk crystals were grown using submerged seed solution method. The structure was elucidated using the single crystal x-ray diffraction data. The compound crystallized in the space group P21 and the unit cell contains a protonated L-methioninium cation and a zwitterionic methionine residue plus a maleate anion. The backbone conformation angles Ψ1 and Ψ2 are in cis and trans configurations for both the methionine and methioninium residues, respectively. Amino and carboxyl groups of the methioninium and methionine residues are connected through N–H...O hydrogen bonds leading to a ring R22(10) motif.
Studies on the growth aspects of organic L-alanine maleate: a promising nonlinear optical crystal  [PDF]
D. Balasubramanian, R. Jayavel, P. Murugakoothan
Natural Science (NS) , 2009, DOI: 10.4236/ns.2009.13029
Abstract: A organic nonlinear optical material, L-alanine maleate (LALM) was synthesized. Bulk Single crystals of LALM have been grown by slow cooling method with a solution pH of 5. The solubility of L-alanine maleate has been deter-mined for various temperatures. Large size sin-gle crystal of 2.0 x 1.2 x 0.8 cm3 has been grown with reasonable growth rate along the three crystallographic directions by optimizing the growth parameters. The structure of LALM crys- tal was studied by single-crystal X-ray diffrac-tion analysis. The presence of functional groups was confirmed by Fourier transform infrared spectroscopy. The LALM crystal was analysed for its thermal and mechanical behaviours. The grown crystals have also been subjected to linear and non-linear optical property studies. From these studies, it is inferred that the LALM crystals exhibit better thermal and mechanical stabilities with improved optical properties. Thus satisfies the essential requirements for optical device fabrication.
The diagnosis of calcium pyrophosphate dihydrate crystal deposition disease: the good, the bad and… ultrasonography!  [cached]
G. Filippou,B. Frediani
Reumatismo , 2012, DOI: 10.4081/reumatismo.2012.125
Abstract: The diagnosis of calcium pyrophosphate dihydrate crystal deposition disease (CPPD) until recent years has been mainly based on the finding of typical crystals of calcium pyrophosphate dihydrate (CPP) in the synovial fluid of affected patients and on the presence of typical calcifications on plain X-rays....
Comparative Study of Pure and Doped Single Crystals of Lead Iodide Dihydrate and Lead Tartrate Dihydrate Grown in Silica Gel Using Fourier Transform Raman Spectra  [PDF]
G. Lillybai,M. H. Rahimkutty
Journal of Atomic and Molecular Physics , 2010, DOI: 10.1155/2010/265403
Abstract: It is presented the FT-Raman spectroscopic investigation of the lead tartrate dihydrate and lead iodide dihydrate.The difference in the spectroscopic behavior of these salts were found which can be attributed to a different geometry of the tartrate and iodide ions. The structural differences between the coordination environments of lead atoms are discussed in connection with Raman frequencies. The compounds have been synthesized using sodium metasilicate gel at ordinary temperature and pressure. 1. Introduction Lead iodide (PbI2) is a very important material with a technological applicability as a room temperature detector. It is a wide-band-gap semiconductor (Eg 2?eV) with high environmental stability efficiency [1–5]. Recently, its band-gap energy and thermal properties were determined by photo acoustic spectroscopy [5, 6]. The electronic and optical properties of lead iodide have been investigated experimentally by means of optical absorption and spectroscopic ellisometry, and theoretically by a full-potential linear muffin-tin-orbital method [7, 8], PbI2 has been recognized as a very promising detector material with large technological applicability [9]. The single crystals of lead iodide have been grown by gel method. The observations of the faces of these crystals revealed that they have grown layer-by-layer as well as spiral mechanisms [7, 8, 10, 11]. In order to study the electronic structure of PbI2 [11–15], the spin-orbit coupling was included. The dielectric function was calculated in the momentum representation [16–18]. From the literature survey shows that there is a very small anisotropy in the optical properties of PbI2 [17–22]. The triangular growth spirals, which are not clearly resolved. But these triangular spirals are seen to be oriented at the site of triangular etch pits produce during the growth processes [23–25]. In fact there is an interlocking of spirals which are oriented anticlockwise and clockwise direction. Lead tartrate initially grew as dendrites because of the large latent heat of crystallization and poor ionic conductivity [26]. The phenomenon of transformation of dendrites into single crystals indicates that it may be useful in the growth of single crystals of materials which normally grow as dendrites. It is now well-established that surface energy and surface diffusion are decisive factors on the shape stability of spherical particles. But the reduction in size is remarkable in the case of cadmium doped crystals. 2. Experimental 2.1. Synthesis of Lead Iodide Single Crystals Dissolve 244?g of sodium metasilicate in
Comparative Study of Pure and Doped Single Crystals of Lead Iodide Dihydrate and Lead Tartrate Dihydrate Grown in Silica Gel Using Fourier Transform Raman Spectra  [PDF]
G. Lillybai,M. H. Rahimkutty
Journal of Atomic, Molecular, and Optical Physics , 2010, DOI: 10.1155/2010/265403
Abstract: It is presented the FT-Raman spectroscopic investigation of the lead tartrate dihydrate and lead iodide dihydrate.The difference in the spectroscopic behavior of these salts were found which can be attributed to a different geometry of the tartrate and iodide ions. The structural differences between the coordination environments of lead atoms are discussed in connection with Raman frequencies. The compounds have been synthesized using sodium metasilicate gel at ordinary temperature and pressure.
Polarized Raman spectra of L-arginine hydrochloride monohydrated single crystal
Faria, J.L.B.;Freire, P.T.C.;Gon?alves, R.O.;Melo, F.E.A.;Mendes Filho, J.;Lima, R.J.C.;Moreno, A.J.D.;
Brazilian Journal of Physics , 2010, DOI: 10.1590/S0103-97332010000300005
Abstract: polarized raman spectra of l-arginine hydrochloride monohydrated single crystal in nine different scattering geometries of the two irreducible representations of factor group c2 were studied at room temperature. the experimental wavenumber values are compared with those obtained from ab-initio calculation and the assignment of the raman bands to the respective molecular vibrations is also given. finally, a discussion related to a previously reported phase transition undergone by l-arginine hydrochloride monohydrated single crystal at low temperature is furnished.
Crystal Structure of Arginine Methyltransferase 6 from Trypanosoma brucei  [PDF]
Chongyuan Wang, Yuwei Zhu, Jiajia Chen, Xu Li, Junhui Peng, Jiajing Chen, Yang Zou, Zhiyong Zhang, Hong Jin, Pengyuan Yang, Jihui Wu, Liwen Niu, Qingguo Gong, Maikun Teng, Yunyu Shi
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0087267
Abstract: Arginine methylation plays vital roles in the cellular functions of the protozoan Trypanosoma brucei. The T. brucei arginine methyltransferase 6 (TbPRMT6) is a type I arginine methyltransferase homologous to human PRMT6. In this study, we report the crystal structures of apo-TbPRMT6 and its complex with the reaction product S-adenosyl-homocysteine (SAH). The structure of apo-TbPRMT6 displays several features that are different from those of type I PRMTs that were structurally characterized previously, including four stretches of insertion, the absence of strand β15, and a distinct dimerization arm. The comparison of the apo-TbPRMT6 and SAH-TbPRMT6 structures revealed the fine rearrangements in the active site upon SAH binding. The isothermal titration calorimetry results demonstrated that SAH binding greatly increases the affinity of TbPRMT6 to a substrate peptide derived from bovine histone H4. The western blotting and mass spectrometry results revealed that TbPRMT6 methylates bovine histone H4 tail at arginine 3 but cannot methylate several T. brucei histone tails. In summary, our results highlight the structural differences between TbPRMT6 and other type I PRMTs and reveal that the active site rearrangement upon SAH binding is important for the substrate binding of TbPRMT6.
Trimipraminium maleate  [cached]
Jerry P. Jasinski,Ray J. Butcher,Q. N. M. Hakim Al-Arique,H. S. Yathirajan
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810000280
Abstract: The title compound [systematic name: 3-(10,11-dihydro-5H-dibenzo[b,f]azepin-5-yl)-N,N,2-trimethylpropan-1-aminium hydrogen maleate], C20H27N2+·C4H3O4 , a maleate salt of trimipramine, crystallizes with four independent cation–anion pairs in the asymmetric unit. The trimipramine cation contains a seven-membered azepine ring with two fused benzene rings whose mean planes are separated by 51.7 (1)°. Intermolecular N—H...O and intramolecular O—H...O hydrogen bonds pack the ions into chains along [101]. Additional weak intermolecular C—H...O interactions help to influence the twist angles of the mean planes of the benzene rings fused to the azepine ring in the cation. A geometry-optimized MOPAC AM1 theoretical calculation supports these observations.
Growth and Solvent Effects of a Promising Nonlinear Optical Sodium Paranitrophenolate Dihydrate (NO2-C6H4-ONa 2H2O) Single Crystal

BMilton Boaz,ALeyo Rajesh,SXavier Jesu Raja,SJerome Das,

材料科学技术学报 , 2004,
Abstract: Sodium paranitrophenolate dihydrate (NPNa 2H2O) is an excellent semiorganic nonlinear optical (NLO) material, crystallizes both in water and methanol with high degree of transparency. Good optical quality single crystals of dimension upto 18 mm×6 mm×3 mm are obtained by sothermal solvent evaporation technique. The solubility of the crystal in different solvents was measured gravimetrically. The single crystals of NPNa 2H2O show variation in physical properties and growth rate in different solvents. Methanol or ethanol solution yields crystals of bipyramidal shape with clear morphology. However, methanol grown crystal is exhibiting improved hardness parameters and possesses excellent thermal stability as compared to water grown crystals. The effects of solvent on hardness parameter along with thermal and optical properties of NPNa 2H2O was revealed in this paper.
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