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1.
Single crystals of tris(thiourea)silver(I) nitrate have been grown by slow evaporation solution growth technique from an aqueous solution at 25 °C. The single crystal X-ray diffraction study reveals that the crystal belongs to tetragonal system and cell parameters are a = b = 14.2790(4) Å, c = 24.8900(7) Å, and V = 5074.8(2) Å3. The various functional groups present in the molecule are confirmed by Fourier transformed infrared spectroscopy (FT-IR). The structure and the crystallinity of the materials were further confirmed by powder X-ray diffraction analysis. Thermogravimetric and differential thermal analysis reveal the purity of the sample and no decomposition is observed up to the melting point. The crystal is further characterized by UV–Vis and Vickers microhardness analysis.  相似文献   

2.
Single crystal of l-asparagine monohydrate (LAM), organic nonlinear optical material has been grown by slow evaporation solution growth technique. Single crystal X-ray diffraction analysis was employed to identify the cell parameters. FT-IR analysis was used to estimate the qualitative presence of the amino acids in the grown crystal. Anisotropy properties like thermal and dielectric properties were studied on the grown crystal. The sample was thermally stable up to 125 °C. Also various thermodynamic properties were calculated and reported for the first time. Optical properties such as optical absorption, second harmonic generation, photoluminescence and photoconductivity analysis were also studied on the grown crystal. Optical absorption studies showed a lower UV cut-off of 225 nm. The SHG efficiency of the sample was seven times higher than that of KDP. Photoluminescence study confirms the suitability of the material for the generation of blue radiation. Multilayer plate-like pattern of growth was observed by scanning electron microscopy. The photoconductivity study confirms that the LAM crystal has negative photoconducting nature.  相似文献   

3.
Single crystals of nonlinear optical material l-glutamic acid hydrochlorobromide (LGHCB) were grown by slow evaporation technique from its aqueous solution. Optically good quality crystals of dimension 20 × 10 × 2 mm3 were obtained. The lattice parameters for the grown crystals were determined using single crystal X-ray diffraction study. The LGHCB crystal belongs to non-centrosymmetric P212121 space group. The crystal structure was resolved by direct method and refined by full matrix least-square method using SHELXL-97. Using the powder X-ray diffraction study, the crystallinity of the grown crystal was confirmed and the diffraction peaks are indexed. From Fourier transform infrared spectroscopy study, the various functional groups present in LGHCB crystal were elucidated. The UV–Vis-NIR absorption spectrum was recorded in the range of 200–2,000 nm, and the lower cut off wavelength is ~235 nm. Optical band gap of the grown crystal was found to be 5.22 eV. Thermal properties of LGHCB crystal were studied by thermogravimetric analysis and derivative thermogravimetric analysis. The second harmonic generation efficiency of LGHCB crystal was confirmed by Kurtz’s powder technique.  相似文献   

4.
A new semi-organic nonlinear optical material glycyl-l-alanine hydrochloride (GLAH) was grown successfully by slow evaporation solution growth method. The solubility of GLAH was estimated for a wide range of temperatures. Large size single crystal of size 15?×?9?×?6?mm3 was grown at room temperature. The grown crystal was subjected to single crystal X-ray diffraction study which confirms that the grown crystal is monoclinic in nature with the space group P21. The molecular weight of the title compound was estimated by mass spectrometry. Functional groups and the modes of vibrations were identified by FT-IR spectral analysis. The UV?Cvisible spectral study reveals that the percentage of optical transmission of the sample is very high in the entire visible and UV regions. The second harmonic generation of the crystal was confirmed by the Kurtz and Perry technique. The hardness of the sample was tested by microhardness test which shows that the grown crystal belongs to the soft category of materials. The thermal stability of the compound was studied by TG?CDTA analyses which indicate that the crystal is thermally stable up to 248.6?°C.  相似文献   

5.
Organic nonlinear optical (NLO) material, N-succinopyridine (NSP), was synthesised and bulk single crystals were grown from aqueous solution using isothermal solvent evaporation technique. The stoichiometric form of NSP has been confirmed by carbon–hydrogen–nitrogen analysis. NSP crystallizes in orthorhombic system with non-centrosymmetric space group P212121 and unit cell dimensions a = 7.721(2) Å, b = 7.762(3) Å, c = 14.951(3) Å. The thermal stability, thermal decomposition and specific heat capacity of NSP have been investigated by thermogravimetric/differential thermal analysis, differential scanning calorimetric (DSC) analysis and modulated DSC analysis. A wide transparency window, 294–1,100 nm, useful for optoelectronic applications is indicated by UV–Vis–NIR studies. The NLO second harmonic generation efficiency analysis using Nd:YAG laser (1,064 nm) revealed that the SHG efficiency of NSP is about 1.2 times higher than that of standard potassium dihydrogen phosphate powder of comparable size and more importantly that it is phase-matchable. The room temperature mechanical behaviours of NSP have been tested using Vicker’s microhardness tester and the results were analysed through classical Mayer’s law. The dielectric behaviours such as dielectric constant, dielectric loss and ac conductivity of NSP single crystal have also been investigated as a function of frequency (20 Hz–1 MHz) and temperature (308–358 K).  相似文献   

6.
New semi-organic bis(thiourea)silver(I)nitrate (TuAgN) single crystals have been grown from slow evaporation solution growth technique. Single crystal X-ray diffraction study reveals that the crystal belongs to orthorhombic system with the non-centrosymmetric space group C2221 and the calculated cell parameters are a = 33.3455 (6) Å, b = 45.2957 (7) Å, c = 20.3209 (5) Å, α = β = γ = 90°, and V = 30692.8 (10) Å 3. The thermal stability and decomposition behavior of TuAgN compound have been studied by thermogravimetric analysis at three different heating rates 5, 10, and 15 °C min?1. The effective activation energy (E a) and pre-exponential factor (ln A) of thermal decomposition of thiourea from TuAgN compound at three different heating rates are estimated by model free methods: Arrhenius, Flynn–Wall, Kissinger, and Kim–Park. The calculated effective activation energies were found to vary with the fraction (α) reacted. The compensation effect between the (ln A) and (E a) has also been studied. Dielectric properties of TuAgN crystal have been studied in a wide range of frequencies and temperatures. AC conductivity has also been carried out.  相似文献   

7.
Bulk single crystals of pure and organic dyes (rhodamine, amaranth, and methyl orange) admixture l-arginine trifluoroacetate were grown by slow evaporation technique. The cell parameters and crystallinity of pure and dyes-mixed LATF were confirmed by powder X-ray diffraction analysis. Thermal analysis (TG/DTA, DSC) reveals the purity of the sample and no decomposition is observed up to melting point. In the TG trace of pure LATF, methyl orange: LATF, amaranth: LATF and rhodamine: LATF it is observed that the crystals were thermally stable up to 488, 485, 483, and 484.14 K, respectively. The crystals are further characterized using UV–Vis analysis, microhardness analysis, and EDAX analysis. By plotting log P versus log d, the value of the work hardening coefficient "n" was found to be 1.95, 0.52, 0.8, and 0.88 for pure, methyl orange, amaranth, and rhodamine dyes-doped LATF grown crystals, respectively. Second harmonic generation efficiency of pure and dye admixture LATF crystals was measured using Kurtz and Perry powder test, the efficiency of methyl orange, amaranth, and rhodamine dyes-doped LATF crystal is 2.7, 2.6, and 2.07 times greater than KDP, where as the efficiency of LATF pure is 2.5 times greater than that of KDP.  相似文献   

8.
A good quality single crystal of Tutton salt, (NH4)2Fe(SO4)2·6H2O, with dimensions 6 × 7 × 3 mm3 was successfully grown by the slow evaporation growth technique at ambient temperature. The grown crystal was subjected to single crystal X-ray diffraction study which confirms that the grown crystal is monoclinic in nature with the space group P21/c. Optical absorption spectrum reveals that the grown crystal has good optical transparency in the entire visible region and its energy band gap was determined. The thermal behavior of the grown crystal was investigated by thermogravimetric and differential thermal analysis. The dielectric measurements were carried out to determine the dielectric behavior of the crystal.  相似文献   

9.
The 1:1 adduct of l-Alanine and sodium bromide (l-ANaBr) crystal has been grown from aqueous solution by a slow evaporation technique. l-alanine and sodium bromide were used in the ratio 1:1 for synthesis. Characterizations were carried out to study the thermal, optical, and mechanical properties of the grown crystal. Single-crystal X- ray diffraction analysis shows that the grown crystal belongs to the monoclinic system. The crystalline nature and its various planes of reflections were observed by powder XRD analysis. Thermal studies reveal that the crystal is stable up to 113.37 °C. The chemical compositions of the grown crystal were determined by FT-IR spectral analysis. The transmittance, absorption, and reflection spectrum of l-ANaBr crystal studied using a UV–Vis spectrometer indicates that the crystal has good optical transparency. The mechanical property of the grown crystal studied using Vickers microhardness measurement reveals that the crystal is a soft material.  相似文献   

10.
Single crystals of (chloro)tris(thiourea-κS)cadmium(II) picrate have been grown by slow evaporation of a mixed solvent system water–acetone containing thiourea, cadmium chloride, and picric acid. The yellow crystals belong to triclinic system with centrosymmetric space group P-1 and the corresponding lattice parameters are a = 7.4632(3) ?, b = 7.9567(3) ?, c = 17.4885(7) ?, α = 98.990(2)°, β = 100.137(2)°, γ = 95.275(2)°, and Z = 2. The vibrational patterns of the as-grown crystals are analyzed by FT-IR and FT-Raman spectral analyses. The optical absorption study was performed to analyze the optical transparency of CTTCP and the crystals were transparent in the visible region and have a lower optical cutoff at ~507 nm with band gap energy of 2.47 eV. TG–DTA thermal analysis shows that the crystal is stable up to ~208 °C and has a good chemical stability.  相似文献   

11.
A novel beryllium borate CsBe4(BO3)3 has been grown in crystals by high-temperature flux method using spontaneous nucleation technique for the first time. The crystal structure of this compound was determined by single crystal X-ray diffraction analysis. It crystallizes in the orthorhombic space group Pnma with lattice parameters a = 8.3914(5) Å, b = 13.3674(7) Å, c = 6.4391(3) Å, Z = 4, V = 722.28(7) Å3. The crystal takes the same structure type as Rb analog based on the units of BO3 triangles and BeO4 tetrahedrons, displaying a three-dimensional tunnel structure with Cs atoms filling in the cages. The IR spectrum confirms the presence of BO3 groups and the UV–vis–IR diffuse reflectance spectrum exhibits this compound has a short UV cut-off edge below 200 nm. Band structures and density of states were calculated.  相似文献   

12.
l-histidinium glutarate monohydrate, an organic nonlinear optical crystal has been successfully grown from deionized water by slow solvent evaporation method at room temperature. Crystal structure and its lattice parameters were identified by single-crystal X-ray diffraction technique. Crystalline perfection of the grown crystal was studied by high-resolution X-ray diffraction rocking curve measurements by employing a multicrystal X-ray diffractometer. FT-IR and FT-Raman spectral studies were employed to identify the presence of various functional groups and mode of vibrations in the crystal. Thermal behavior of the crystal was studied by TG–DTA, TG–DTG, and DSC analyses. Optical absorption of the crystal in the wavelength region 200–1,000 nm was studied by UV–Vis–NIR spectral analysis. Kurtz and Perry powder technique was employed to find the second harmonic generation efficiency of the crystal.  相似文献   

13.
l-Proline thiourea monohydrate nonlinear optical single crystal of size 65 × 15 mm2 was grown by slow evaporation technique at room temperature. The grown crystal was characterised by single crystal XRD, absorption spectrum, FTIR, EDAX, Vicker’s microhardness test, DSC, dielectric and photoconductivity studies. Second harmonic generation efficiency of the grown crystal makes it a higher order second harmonic material with good conversion efficiency. The reported crystal is an efficient nonlinear optical material with good optical transparency, thermal, mechanical strength and dielectric property.  相似文献   

14.
《Solid State Sciences》2012,14(7):773-776
Single crystal growth, spectroscopic, relative second harmonic generation (SHG) efficiency and thermal analysis of 2-aminopyridinium picrate (2APP) is reported for the first time. Crystals were grown by the slow evaporation solution technique using methanol as a solvent. The crystal system and lattice parameters were confirmed by single crystal and powder XRD analyses. FT-IR and FT-Raman spectroscopic studies were carried out to identify the functional groups and vibrational modes present in the grown crystal. Crystalline perfection of the grown crystal was assessed by high-resolution XRD and the results reveal that the crystal is reasonably good. SHG efficiency was measured using Kurtz powder technique. Thermogravimetric (TG) and differential thermal analysis (DTA) studies were carried out and show that the grown single crystal is stable up to 223 °C.  相似文献   

15.
Single crystals of melaminium bis (hydrogen oxalate) (MOX) single crystals have been grown from aqueous solution by slow solvent evaporation method at room temperature. X-ray powder diffraction analysis confirms that MOX crystallises in monoclinic system with space group C2/c. The calculated lattice parameters are a = 20.075 ± 0.123 Å b = 8.477 ± 0.045 Å, c = 6.983 ± 0.015 Å, α = 90°, β = 102.6 ± 0.33°, γ = 90° and V = 1,159.73 (Å)3. Thermogravimetric analysis at three different heating rates 10, 15 and 20 °C min?1 has been done to study the thermal decomposition behaviour of the crystal. Non-isothermal studies on MOX reveal that the decomposition occurs in two stages. Kinetic parameters [effective activation energy (E a), pre-exponential factor (ln A)] of each stage were calculated by model-free method: Kissinger, Kim–Park and Flynn–Wall method and the results are discussed. A significant variation in effective activation energy (E a) with conversion progress (α) indicates that the process is kinetically complex. The linear relationship between the ln A and E a was established (compensation effect). DTA analyses were conducted at different heating rates and the activation energy was determined graphically from Kissinger and Ozawa equation. The average effective activation energy is calculated as 276 kJ mol?1 for the crystallization peak. The Avrami exponent for the crystallization peak temperature determined by Augis and Bennett method is found to be 1.95. This result indicates that the surface crystallization dominates overall crystallization. Dielectric study has also been done, and it is found that both dielectric constant and dielectric loss decreases with increase in frequency and is almost a constant at high frequency region.  相似文献   

16.
Nonlinear optical single crystal l-tryptophan hydrogen selenite (LTHS) has been synthesized by slow evaporation solution growth technique from aqueous solution at ambient temperature. The grown nonlinear optical crystals were subjected to single crystal XRD analysis to find the structure parameters. The formation of the product was confirmed from the FTIR and 1HNMR spectral analysis. The UV–Vis spectral studies showed that the cutoff wavelength for LTHS was less than 400 nm. The thermal behavior of the grown crystals was investigated from thermogravimetry and differential thermal analysis. Its nonlinear optical property has been tested by Kurtz–Perry powder technique using Nd:YAG laser, and the crystal exhibited second harmonic generation property.  相似文献   

17.
Pyrimidines and its derivatives find different pharmaceutical applications. The n-butyl 4-(3,4 dimethoxyphenyl)-6-methyl-2-thioxo-1,2,3,4 tetrahydropyrimidine-5-carboxylate (abbreviated as n-butyl THPM) was synthesized. The n-butyl THPM crystals were grown by slow solvent evaporation technique using chloroform as a solvent. Yellowish, coagulated, and semi-transparent crystals having dimensions of 2 × 1.5 mm were grown. The crystals were characterized by powder XRD, FT–IR, SEM, TG–DTA–DSC, 1H-NMR, and dielectric study. The crystals remained stable up to 150 °C and then started decomposing. The DSC suggested both endothermic and exothermic reactions. One broad exothermic peak was observed at 540.3 °C due to complete decomposition of the sample into the gaseous phase and reaction within the products. 1H-NMR spectrum has been carried out to explain the molecular structure. The dielectric study was carried out in the frequency range from 50 Hz to 5 MHz at room temperature. The dielectric constant decreased as the frequency of the applied field increased. The variations of dielectric loss, a.c. conductivity, and a.c. resistivity were also studied with the frequency of the applied field.  相似文献   

18.
3-(2,3-Dimethoxyphenyl)-1-(pyridin-2-yl)prop-2-en-1-one (DMPP) a potential second harmonic generating (SHG) has been synthesized and grown as a single crystal by the slow evaporation technique at ambient temperature. The structure determination of the grown crystal was done by single crystal X-ray diffraction study. DMPP crystallizes with orthorhombic system with cell parameters a = 20.3106(8) Å, b = 4.9574(2) Å, c = 13.4863(5) Å, α = 90°, β = 90°, γ = 90° and space group Pca21. The crystals were characterized by FT-IR, thermal analysis, UV–vis–NIR spectroscopy and SHG measurements. Various functional groups present in DMPP were ascertained by FTIR analysis. DMPP is thermally stable up to 80 °C and optically transparent in the visible region. The crystal exhibits SHG efficiency comparable to that of KDP.  相似文献   

19.
A new nonlinear optical crystal urea thiourea cadmium sulfate (UTCS) has been grown by slow evaporation technique in equimolar ratio. The grown crystals were characterized by single crystal X-ray diffraction analysis which reveals that sample crystallizes in triclinic system with non-centrosymmetric space group P1. The powder XRD pattern revealed the formation of UTCS compound. High-resolution-X-ray diffraction analysis was carried out to study the crystalline perfection of the sample. Functional groups of the grown crystal were identified by FT-IR studies. Thermo gravimetric and differential thermal analyses were employed to understand the thermal and physio-chemical stability of the synthesized compound. UV–Vis–NIR spectrum revealed the transmission properties of the crystal specimen. The SHG efficiency has been tested by the Kurtz powder technique using Nd: YAG laser and found to be about 0.82 times in comparison with standard KDP crystals.  相似文献   

20.
A new semiorganic single crystal, tris(allylthiourea)silver(I) nitrate was grown from an aqueous solution containing silver(I) nitrate and allylthiourea by slow evaporation solution growth technique at room temperature. The crystal belongs to trigonal system with centrosymmetric space group R3 and the cell parameters are, a = 12.5090(4) Å, b = 12.5090(4) Å, c = 21.7130(8) Å, V = 3348.89 Å3, and Z = 6. The various functional groups present in the molecule are confirmed by Fourier transformed infrared spectroscopy. High transmittance is observed in the visible region and band-gap energy is calculated by Kubelka–Munk algorithm. The structure and the crystallinity of the materials were further confirmed using powder X-ray diffraction analysis. Microhardness studies were also carried out to elucidate the mechanical behavior. Thermogravimetric and differential thermal analysis reveal the purity of the sample and no decomposition is observed up to the melting point.  相似文献   

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