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Horacio N Solimo - One of the best experts on this subject based on the ideXlab platform.
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spectroscopic and thermodynamic evidence of dimer and trimer hydrogen bonded complex formation between chloroform and 2 butanone excess molar enthalpy for the chloroform 2 butanone binary system at 303 k
Journal of Physical Chemistry B, 2013Co-Authors: Ana Gomez C Marigliano, Viviana Del V Campos, Lis Fernandez, M L Roldan, Horacio N SolimoAbstract:FT-Raman and FT-infrared spectra of pure chloroform (A) and 2-butanone (B), as well as of the binary system chloroform + 2-butanone, were recorded to investigate the type and nature of the intermolecular complexes formed when both chemicals are mixed. The optimized structures and vibrational frequencies for 2-butanone, chloroform, and their 1:1 and 1:2 complexes were calculated by means of density functional theory (DFT) techniques using the B3LYP functional combined with the 6-31G(d,p) and 6-311++G(d,p) basis set. The recorded FTIR and Raman spectra confirm the existence of these types of hydrogen-bonded complexes, making it possible, furthermore, to calculate the heteroassociation constants. Heat of Mixing at 303 K over the whole mole fraction range at atmospheric pressure was also measured. The excess molar enthalpy was fitted to a Redlich–Kister-type equation, using least-squares to obtain its dependence on concentration. The ideal associated solution model was also used to calculate these equilibrium...
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density viscosity refractive index excess molar enthalpy viscosity and refractive index deviations for the 1 butanol 2 butanone binary system at t 303 k a new adiabatic calorimeter for Heat of Mixing
The Journal of Chemical Thermodynamics, 2008Co-Authors: Rene A Clara, Ana Gomez C Marigliano, Horacio N SolimoAbstract:Abstract Density, viscosity, refractive index, and Heat of Mixing measurements for {x1 1-butanol + (1 − x1) 2-butanone} at T = 303 K were made over the whole concentration range. Data of the binary mixture were further used to calculate the viscosity and refractive index deviations, and excess molar enthalpy. The excess or deviation properties were fitted with the Redlich–Kister polynomial relation to obtain their coefficients and standard deviations. The construction of an adiabatic calorimeter useful in the neighbourhood of room temperature is described. Its performance was checked by measuring the Heat of Mixing for {x1 benzene + (1 − x1) cyclohexane} over the whole concentration range at T = 298 K. Experimental results are within a standard deviation of 9 J · mol−1 of the accepted literature values.
Ana Gomez C Marigliano - One of the best experts on this subject based on the ideXlab platform.
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spectroscopic and thermodynamic evidence of dimer and trimer hydrogen bonded complex formation between chloroform and 2 butanone excess molar enthalpy for the chloroform 2 butanone binary system at 303 k
Journal of Physical Chemistry B, 2013Co-Authors: Ana Gomez C Marigliano, Viviana Del V Campos, Lis Fernandez, M L Roldan, Horacio N SolimoAbstract:FT-Raman and FT-infrared spectra of pure chloroform (A) and 2-butanone (B), as well as of the binary system chloroform + 2-butanone, were recorded to investigate the type and nature of the intermolecular complexes formed when both chemicals are mixed. The optimized structures and vibrational frequencies for 2-butanone, chloroform, and their 1:1 and 1:2 complexes were calculated by means of density functional theory (DFT) techniques using the B3LYP functional combined with the 6-31G(d,p) and 6-311++G(d,p) basis set. The recorded FTIR and Raman spectra confirm the existence of these types of hydrogen-bonded complexes, making it possible, furthermore, to calculate the heteroassociation constants. Heat of Mixing at 303 K over the whole mole fraction range at atmospheric pressure was also measured. The excess molar enthalpy was fitted to a Redlich–Kister-type equation, using least-squares to obtain its dependence on concentration. The ideal associated solution model was also used to calculate these equilibrium...
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density viscosity refractive index excess molar enthalpy viscosity and refractive index deviations for the 1 butanol 2 butanone binary system at t 303 k a new adiabatic calorimeter for Heat of Mixing
The Journal of Chemical Thermodynamics, 2008Co-Authors: Rene A Clara, Ana Gomez C Marigliano, Horacio N SolimoAbstract:Abstract Density, viscosity, refractive index, and Heat of Mixing measurements for {x1 1-butanol + (1 − x1) 2-butanone} at T = 303 K were made over the whole concentration range. Data of the binary mixture were further used to calculate the viscosity and refractive index deviations, and excess molar enthalpy. The excess or deviation properties were fitted with the Redlich–Kister polynomial relation to obtain their coefficients and standard deviations. The construction of an adiabatic calorimeter useful in the neighbourhood of room temperature is described. Its performance was checked by measuring the Heat of Mixing for {x1 benzene + (1 − x1) cyclohexane} over the whole concentration range at T = 298 K. Experimental results are within a standard deviation of 9 J · mol−1 of the accepted literature values.
R N Rai - One of the best experts on this subject based on the ideXlab platform.
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green synthesis characterization and optical properties of eutectics and 1 1 intermolecular compounds n n dimethylaminobenzaldehyde anthranilic acid and 2 4 dimethylamino benzylideneamino benzoic acid p nitroaniline systems
Bulletin of Materials Science, 2019Co-Authors: U S Rai, Manjeet Singh, R N RaiAbstract:Phase diagrams of N, N-dimethylaminobenzaldehyde (DMAB)–anthranilic acid (AA) and 2-(4-(dimethylamino)benzylideneamino)benzoic acid (DMABAB)–p-nitroaniline (PNA) systems, determined by the thaw-melt method, give two eutectics and a 1:1 intermolecular compound (IMC) in each case. Appropriate amounts (10 g) of each of the eutectics and the IMCs were prepared by a green synthetic method involving a solid state reaction without any solvent. These materials were characterized by X-ray diffraction, thermal and spectral methods and the optical properties of the pure components and the IMCs were studied. While negative values of Heat of Mixing in the case of a DMAB–AA system suggest clustering of molecules in both eutectic melts, those of positive value in $$\hbox {E}_{1}$$ and negative value in $$\hbox {E}_{2}$$ of the DMABAB–PNA system indicate the formation of a quasi-eutectic structure in $$\hbox {E}_{1}$$ melt and clustering of molecules in $$\hbox {E}_{2}$$ melt. The IMC of DMAB–AA system shows strong dual emission with two $$\lambda _{\mathrm{max}} $$ one at 380 nm and the second at 450 nm with a total quantum efficiency of 0.49. The IMC of DMABAB–PNA system also shows a similar observation with two $$\lambda _{\mathrm{max}} $$ one at 390 nm and second at 435 nm with a total quantum efficiency of 0.31.
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synthesis crystal growth and physicochemical studies on a novel organic inter molecular compound 3 5 dinitrobenzoic acid and salicylamide system
Journal of Crystal Growth, 2015Co-Authors: Manjeet Singh, R N Rai, U S RaiAbstract:Abstract The phase diagram of salicylamide (SAM) and 3,5-dinitrobenzoic acid (DNBA) system was determined by the thaw-melt method. Results show the formation of an inter-molecular compound and two eutectics. The values of Heat of Mixing, entropy of fusion, roughness parameter, interfacial energy, and the excess thermodynamic functions were calculated from the enthalpy of fusion data determined by the differential scanning calorimetric (DSC) method. The spectroscopic investigations (IR and NMR) suggest the presence of hydrogen bonding between the components of the compound. A single crystal of the inter-molecular compound was grown using slow cooling technique from the mixed solvent of ethanol and triple distilled water in 2:1 volume ratio. The single crystal analysis and the atomic packing pattern of the grown crystal confirm the monoclinic crystal structure with P 2 1 /c space group. The solubility of the inter-molecular compound was determined in the mixed solvent at different temperatures. Using solubility and entropy of fusion data, the entropy of dissolution and Heat of Mixing were calculated. The optical transmittance spectra of the crystal of the inter-molecular compound show 75% transmittance and the band gap of the crystal was found to be 3.00 eV. The refractive index of the crystal was computed to be 2.50 at the cut off wavelength.
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solid liquid equilibrium thermal and physicochemical studies on salicylamide 4 nitrophenol and 2 cyanoacetamide 4 aminoacetophenone organic eutectic systems
Journal of Thermal Analysis and Calorimetry, 2013Co-Authors: Manjeet Singh, R N Rai, Priyanka Pandey, U S RaiAbstract:The solid–liquid phase equilibrium data of two binary organic systems, namely, salicylamide–4-nitrophenol and 2-cyanoacetamide–4-aminoacetophenone show the formation of a eutectic in each case. The values of enthalpy of fusion of pure components and binary eutectics have been determined using differential scanning calorimeter (Mettler DSC-4000 system). The thermal properties of the materials, such as, Heat of Mixing, entropy of fusion, roughness parameter, interfacial energy, and excess thermodynamic functions were computed using the enthalpy of fusion values. The microstructures of eutectics were developed using unidirectional thermal gradient, and regions of interest for microstructures were photographed.
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phase equilibria crystallization thermal and microstructural studies on organic monotectic analog of nonmetal nonmetal system urea 4 bromo 2 nitroaniline
Fluid Phase Equilibria, 2012Co-Authors: R S B Reddi, S Ganesamoorthy, P K Gupta, R N RaiAbstract:Abstract The phase diagram of urea–4-bromo-2-nitroaniline system was studied which shows a large miscibility gap and the formation of a eutectic and a monotectic where the mole fractions of 4-bromo-2-nitroaniline are 0.899 and 0.020, respectively. The critical temperature is being 61.5 °C above the monotectic horizontal. The formation of solid solution of 4-bromo-2-nitroaniline in urea was studied by powder X-ray diffraction technique. Using differential scanning calorimetry (DSC), the enthalpies of fusion of the pure components, the eutectic and the monotectic were determined. The different thermodynamic parameters such as Heat of Mixing, entropy of fusion, roughness parameter, interfacial energy and excess thermodynamic functions were calculated utilizing the Heat of fusion values. The solid–liquid interfacial energy has also been calculated and their effects on morphological change of microstructure of monotectic and eutectic have been discussed.
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thermal miscibility gap and microstructural studies of organic analog of metal nonmetal system p dibromobenzene succinonitrile
Thermochimica Acta, 2002Co-Authors: R N Rai, U S Rai, K B R VarmaAbstract:The two immiscible liquid phases in equilibrium with a single liquid phase have been observed during the phase diagram study of an organic analog of a metal-nonmetal system, involving p-dibromobenzene-succinonitrile (DBB-SCN). The phase equilibrium shows the formation of a eutectic and a monotectic, with large miscibility gap in the system, contain 0.982 and 0.057 mole fractions of SCN, respectively, and the consolute temperature is 110 degreesC above the monotectic horizontal. The Heat of Mixing, entropy of fusion, roughness parameter, interfacial energy and excess thermodynamic functions were calculated based on enthalpy of fusion data determined via differential scanning calorimeter (DSC) method. The solid-liquid interfacial energy and its effect on morphological change of monotectic structure have been discussed as well as the interfacial energy balance between the solid and two liquids in the monotectic reaction. Whereas the microstructures of monotectic and eutectic show peculiar characteristic features.
Paul E Smith - One of the best experts on this subject based on the ideXlab platform.
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a comparison of the properties of 2 2 2 trifluoroethanol and 2 2 2 trifluoroethanol water mixtures using different force fields
Journal of Chemical Physics, 2001Co-Authors: Rajappa Chitra, Paul E SmithAbstract:It is necessary to evaluate the quality of a force field by comparison with known experimental properties before it can be used with confidence in a simulation. Here, such a study is reported for pure 2,2,2-trifluoroethanol (TFE) solutions and for TFE/water mixtures at two different compositions. Six literature force fields were examined using molecular dynamics simulations. It is found that none of the currently available force fields describe all the properties of pure liquid TFE. The models of van Buren and Berendsen, Duffy and Jorgensen, and Fioroni et al. produce properties that are in reasonable agreement with experiment. The ability to adequately describe properties of TFE/water mixtures varied with the property of interest. The Heat of Mixing is too unfavorable for all the models. The aggregation properties of the mixtures were well described by the model of Duffy and Jorgensen at the lower composition (30% by volume of TFE), while the Fioroni et al. model performed better at higher TFE concentrat...
Rajappa Chitra - One of the best experts on this subject based on the ideXlab platform.
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a comparison of the properties of 2 2 2 trifluoroethanol and 2 2 2 trifluoroethanol water mixtures using different force fields
Journal of Chemical Physics, 2001Co-Authors: Rajappa Chitra, Paul E SmithAbstract:It is necessary to evaluate the quality of a force field by comparison with known experimental properties before it can be used with confidence in a simulation. Here, such a study is reported for pure 2,2,2-trifluoroethanol (TFE) solutions and for TFE/water mixtures at two different compositions. Six literature force fields were examined using molecular dynamics simulations. It is found that none of the currently available force fields describe all the properties of pure liquid TFE. The models of van Buren and Berendsen, Duffy and Jorgensen, and Fioroni et al. produce properties that are in reasonable agreement with experiment. The ability to adequately describe properties of TFE/water mixtures varied with the property of interest. The Heat of Mixing is too unfavorable for all the models. The aggregation properties of the mixtures were well described by the model of Duffy and Jorgensen at the lower composition (30% by volume of TFE), while the Fioroni et al. model performed better at higher TFE concentrat...
