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W V Steele - One of the best experts on this subject based on the ideXlab platform.
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thermodynamic properties of the methylpyridines part 2 vapor pressures heat capacities critical properties derived thermodynamic functions between the temperatures 250 k and 560 k and equilibrium isomer distributions for all temperatures 250 k
The Journal of Chemical Thermodynamics, 1999Co-Authors: Robert D Chirico, S E Knipmeyer, A Nguyen, W V SteeleAbstract:Abstract Results are reported for measurements leading to the calculation of standard thermodynamic properties for temperatures fromT = 250 K toT = 560 K for the methylpyridines (Chemical Abstracts registry numbers: 4-Methylpyridine, 108-89-4; 2-methylpyridine, 109-06-8; 3-methylpyridine, 108-99-6). The standard state is defined as the ideal gas at the pressurep = p° = 101.325 kPa. Vapor pressures were measured by comparative ebulliometry for the pressure rangep ≈ 4 kPa top = 270 kPa. Two-phase ( liquid+vapor) heat capacities were measured for the temperature range ≈ 310
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thermodynamic properties of the methylpyridines part 1 heat capacity measurements for 4 methylpyridine betweent 6 4 k andt 18 6 k resolution of low temperature contributions and reconciliation of calorimetrically and spectroscopically derived standard entropies
The Journal of Chemical Thermodynamics, 1999Co-Authors: Robert D Chirico, S E Knipmeyer, W V SteeleAbstract:Abstract Heat capacities and enthalpy increments between the temperatures 6.4 K and 320 K were determined for 4-Methylpyridine (Chemical Abstract registry number 108-89-4) by adiabatic calorimetry. Results for temperatures ≥ 20 K were found to be in excellent accord with literature values; however, accord forT
Saeid Amani - One of the best experts on this subject based on the ideXlab platform.
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Colorimetric Detection of Pollutant Trivalent Cations and HSO4− in Aqueous Media Using a New Schiff-base Probe: An Experimental and DFT Studies
2019Co-Authors: Masoumeh Orojloo, Saeid AmaniAbstract:In the present study, a novel colorimetric Schiff-base receptor 4-((2-nitrophenyl) diazenyl)-2-((3-methylpyridin-2-ylimino)methyl)phenol was successfully synthesized via the condensation reaction of an azo-coupled precursor to 2-amino-3-methylpyridine in absolute ethanol and a good yield. The probe provided the selective detection of trivalent Cr3+, Fe3+, and Al3+ cations with different color changes. The binding constants of complexation (ka), the molar absorption coefficient (ɛ), and the limit of detection parameters of trivalent ions were measured for Cr3+, Fe3+, and Al3+. The results revealed a high sensitivity for the selective detection of Fe3+ ions. Moreover, the devised receptor rapidly detected the HSO4− anion through absorption spectra and color changes. The HSO4− and Al3+ coordination properties were checked by the 1HNMR titration method. The sensing behavior of the L receptor was further emphasized in computational studies. Accordingly, quantum-chemical studies via Density Functional Theory (DFT) were carried out using the 6–31 + G (d) basis set of the Gaussian 03 program package in order to more supplement the detecting behavior of the L receptor in case of HSO4− anions. The HSO4− and Al3+ coordination properties were investigated by the 1HNMR titration.
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four new co ii complexes with 2 amino 4 methylpyridine 2 amino 3 methylpyridine or 2 amino 5 chloropyridine synthesis spectroscopy magnetic properties and crystal structure
Journal of Coordination Chemistry, 2011Co-Authors: Raziyeh Arab Ahmadi, Nasser Safari, Hamid Reza Khavasi, Saeid AmaniAbstract:Solid-state structures for a series of [Co(L)2X2] complexes are assigned on the basis of magnetic moments, FTIR spectra, electronic spectra properties (L = 2-amino-4-Methylpyridine, 2-amino-3-methylpyridine, or 2-amino-5-chloropyridine; X = chloride or acetate). All complexes were prepared in one-step syntheses. The crystal structure of 2-amino-4-Methylpyridine with cobalt(II) chloride [Co(L)2(Cl)2] was solved at room temperature. This compound consists of mononuclear units consisting of two ligands linked to cobalt via the pyridine. The complex crystallizes in the orthorhombic system, space group Pcan with z = 8. UV-Vis spectra show five absorption bands, attributed to d–d transitions of cobalt, ligand → metal charge transfer, and π → π* or n → π* transitions of ligand. FTIR spectra show CoL2X2 vibrations at 550–300 cm−1. The compounds show room temperature magnetic moments of 4.58–5.29 B.M., indicating high-spin cobalt(II).
Chancheng Su - One of the best experts on this subject based on the ideXlab platform.
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electronic and bonding properties of mixed ligand copper ii complexes of n 2 picolyl picolinamide pmpa x ray crystal structures of cu pmpa 4 methylimidazole h2o h2o clo4 and cu pmpa 4 methylpyridine h2o h2o clo4
Polyhedron, 1997Co-Authors: Chiouyuh Wu, Chancheng SuAbstract:Abstract Mixed-ligand N -(2-picolyl)picolinamidocopper(II) complexes, [Cu(pmpa)(L)(X) · n H 2 O] [pmpa = N -(2-picolyl)picolinamide anion; L = imidazole ( n = 0, o or 2), N -methylimidazole ( n = 0 or 1), 4-methylimidazole (4MImH) ( n = 0 or 2), pyridine ( n = 0), 2-methylpyridine ( n = 0), 3-methylpyridine ( n = 0), 4-Methylpyridine (4Mpy) ( n = 2), and NH 3 ( n = 2); X = ClO 4 − or BF 4 − ], have been synthesized and characterized by elemental analyses, and electronic, vibrational, and EPR spectroscopic measurements. Molecular structures of [Cu(pmpa)(4MImH)(H 2 O)](H 2 O)](H 2 O)(ClO 4 ( 1 ) and [Cu(pmpa)(4Mpy)(H 2 O)](H 2 O)(ClO 4 ) ( 2 ) have been determined by X-ray diffraction methods. Both complexes are square pyramidal with the pmpa and the heterocyclic unidentate ligands forming the basal plane and a H 2 O molecule on the apical position. The dihedral angles of the heterocyclic unidentate nucleus and the CuN 4 basal plane are 79.3° for 1 and 74.5° for 2 . The structures of other pmpa complexes are suggested to be square pyramidal or square planar based on their spectroscopic data. The sequence of d orbitals is assigned as d x 2 − y 2 ⪢ d z 2 > d yz > d xy > d xz for the square pyramidal complexes and d x 2 − y 2 ⪢ d yz > d xy > d xz > d z 2 for the square planar complexes. The significant rise in energy of the d yz orbital suggests that the central amido of the pmpa ligand is a strong π-donor.
Robert D Chirico - One of the best experts on this subject based on the ideXlab platform.
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thermodynamic properties of the methylpyridines part 2 vapor pressures heat capacities critical properties derived thermodynamic functions between the temperatures 250 k and 560 k and equilibrium isomer distributions for all temperatures 250 k
The Journal of Chemical Thermodynamics, 1999Co-Authors: Robert D Chirico, S E Knipmeyer, A Nguyen, W V SteeleAbstract:Abstract Results are reported for measurements leading to the calculation of standard thermodynamic properties for temperatures fromT = 250 K toT = 560 K for the methylpyridines (Chemical Abstracts registry numbers: 4-Methylpyridine, 108-89-4; 2-methylpyridine, 109-06-8; 3-methylpyridine, 108-99-6). The standard state is defined as the ideal gas at the pressurep = p° = 101.325 kPa. Vapor pressures were measured by comparative ebulliometry for the pressure rangep ≈ 4 kPa top = 270 kPa. Two-phase ( liquid+vapor) heat capacities were measured for the temperature range ≈ 310
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thermodynamic properties of the methylpyridines part 1 heat capacity measurements for 4 methylpyridine betweent 6 4 k andt 18 6 k resolution of low temperature contributions and reconciliation of calorimetrically and spectroscopically derived standard entropies
The Journal of Chemical Thermodynamics, 1999Co-Authors: Robert D Chirico, S E Knipmeyer, W V SteeleAbstract:Abstract Heat capacities and enthalpy increments between the temperatures 6.4 K and 320 K were determined for 4-Methylpyridine (Chemical Abstract registry number 108-89-4) by adiabatic calorimetry. Results for temperatures ≥ 20 K were found to be in excellent accord with literature values; however, accord forT
Raziyeh Arab Ahmadi - One of the best experts on this subject based on the ideXlab platform.
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four new co ii complexes with 2 amino 4 methylpyridine 2 amino 3 methylpyridine or 2 amino 5 chloropyridine synthesis spectroscopy magnetic properties and crystal structure
Journal of Coordination Chemistry, 2011Co-Authors: Raziyeh Arab Ahmadi, Nasser Safari, Hamid Reza Khavasi, Saeid AmaniAbstract:Solid-state structures for a series of [Co(L)2X2] complexes are assigned on the basis of magnetic moments, FTIR spectra, electronic spectra properties (L = 2-amino-4-Methylpyridine, 2-amino-3-methylpyridine, or 2-amino-5-chloropyridine; X = chloride or acetate). All complexes were prepared in one-step syntheses. The crystal structure of 2-amino-4-Methylpyridine with cobalt(II) chloride [Co(L)2(Cl)2] was solved at room temperature. This compound consists of mononuclear units consisting of two ligands linked to cobalt via the pyridine. The complex crystallizes in the orthorhombic system, space group Pcan with z = 8. UV-Vis spectra show five absorption bands, attributed to d–d transitions of cobalt, ligand → metal charge transfer, and π → π* or n → π* transitions of ligand. FTIR spectra show CoL2X2 vibrations at 550–300 cm−1. The compounds show room temperature magnetic moments of 4.58–5.29 B.M., indicating high-spin cobalt(II).
