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Articles de revues sur le sujet « Thermochemistry - Molecules »

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Auteur : Grafiati
Publié le 7 septembre 2023

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1

Gu, Geun Ho, Petr Plechac et Dionisios G. Vlachos. « Thermochemistry of gas-phase and surface species via LASSO-assisted subgraph selection ». Reaction Chemistry & ; Engineering 3, no 4 (2018) : 454–66. http://dx.doi.org/10.1039/c7re00210f.

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RAGHAVACHARI, KRISHNAN, BORIS STEFANOV et LARRY CURTISS. « Accurate density functional thermochemistry for larger molecules ». Molecular Physics 91, no 3 (20 juin 1997) : 555–59. http://dx.doi.org/10.1080/00268979709482745.

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RAGHAVACHARI, By KRISHNAN, BORIS B. STEFANOV et LARRY A. CURTISS. « Accurate density functional thermochemistry for larger molecules ». Molecular Physics 91, no 3 (juin 1997) : 555–60. http://dx.doi.org/10.1080/002689797171445.

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Haworth, Naomi L., Michael B. Sullivan, Angela K. Wilson, Jan M. L. Martin et Leo Radom. « Structures and Thermochemistry of Calcium-Containing Molecules ». Journal of Physical Chemistry A 109, no 40 (octobre 2005) : 9156–68. http://dx.doi.org/10.1021/jp052889h.

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Bouchoux, Guy, Danielle Leblanc, William Bertrand, Terance B. McMahon, Jan E. Szulejko, Florence Berruyer-Penaud, Otilia Mó et Manuel Yáñez. « Protonation Thermochemistry of Selected Hydroxy- and Methoxycarbonyl Molecules ». Journal of Physical Chemistry A 109, no 51 (décembre 2005) : 11851–59. http://dx.doi.org/10.1021/jp054955l.

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Griller, David, J. A. Martinho Simoes, P. Mulder, B. A. Sim et D. D. M. Wayner. « Unifying the solution thermochemistry of molecules, radicals, and ions ». Journal of the American Chemical Society 111, no 20 (septembre 1989) : 7872–76. http://dx.doi.org/10.1021/ja00202a031.

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Bross, David H., et Kirk A. Peterson. « Composite thermochemistry of gas phase U(VI)-containing molecules ». Journal of Chemical Physics 141, no 24 (28 décembre 2014) : 244308. http://dx.doi.org/10.1063/1.4904721.

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Nagy, Balázs, Péter Szakács, József Csontos, Zoltán Rolik, Gyula Tasi et Mihály Kállay. « High-Accuracy Theoretical Thermochemistry of Atmospherically Important Sulfur-Containing Molecules ». Journal of Physical Chemistry A 115, no 26 (7 juillet 2011) : 7823–33. http://dx.doi.org/10.1021/jp203406d.

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Barreto, Patr�cia R. P., Alessandra F. A. Vilela et Ricardo Gargano. « Thermochemistry of molecules in the B/F/H/N system ». International Journal of Quantum Chemistry 103, no 5 (2005) : 659–84. http://dx.doi.org/10.1002/qua.20566.

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Karton, Amir. « A computational chemist's guide to accurate thermochemistry for organic molecules ». Wiley Interdisciplinary Reviews : Computational Molecular Science 6, no 3 (15 février 2016) : 292–310. http://dx.doi.org/10.1002/wcms.1249.

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11

Poon, Clement, et Paul M. Mayer. « Electron-spin conservation and methyl-substitution effects on bonds in closed- and open-shell systems — A G3 ab initio study of small boron-containing molecules and radicals ». Canadian Journal of Chemistry 80, no 1 (1 janvier 2002) : 25–30. http://dx.doi.org/10.1139/v01-185.

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High level ab initio molecular orbital theory calculations have been used to study the geometries and thermochemistry of molecules and free radicals substituted by BH2, BHCH3, and B(CH3)2. The heats of formation and RR'B—X bond strengths (RR' = H, H; H, CH3; CH3, CH3 and X = CH3, NH2, OH, F, SiH3, PH2, SH, and Cl) together with those for the open-shell systems RR'B—Y· (RR' = H, H; H, CH3; CH3, CH3 and Y = CH2, NH, O, SiH2, PH, and S) have been calculated at the G3 level of theory. The trends observed for the homolytic bond strengths in the closed-shell systems are those expected from electronegativity arguments, i.e., as the difference in electronegativity between the two atoms in the B—X bond increases, the bond strength increases. Methyl substitution on B in the closed- and open-shell species increases the ionic contribution to the bond thereby decreasing the bond strength. The lowest possible homolytic dissociation energy for the free radicals RR'BY· is lower than those of their closed-shell counterparts, yet the B—Y· bonds are shorter. This is due to the demands of spin conservation in the dissociation of the radicals favouring the formation of higher energy products.Key words: ab initio calculations, bond dissociation energy, organoboron compounds, thermochemistry.
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Roux, María Victoria, Concepción Foces-Foces et Rafael Notario. « Thermochemistry of organic molecules : The way to understand energy–structure relationships ». Pure and Applied Chemistry 81, no 10 (3 octobre 2009) : 1857–70. http://dx.doi.org/10.1351/pac-con-08-10-01.

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The combination of experimental calorimetric measurements, particularly of the standard energies and enthalpies of combustion and formation, and theoretical examination of model molecules constitutes a powerful tool for the understanding of the conformational and chemical behavior of organic molecules. In this article, several examples are provided where the synergy between experiment and theory made possible the comprehension of various fundamental interactions in oxygen- and sulfur-containing six-membered heterocyclic compounds, the determination of the strain energy in two C8H8 derivatives, dimethyl cubane-1,4-dicarboxylate and dimethyl cuneane-2,6-dicarboxylate, and the calculation of the enthalpies of formation of the parent compounds, cubane and cuneane, and the study of the energy–structure relationship in barbituric acid.
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Zachariah, Michael R., et Carl F. Melius. « Theoretical Calculation of Thermochemistry for Molecules in the Si−P−H System ». Journal of Physical Chemistry A 101, no 5 (janvier 1997) : 913–18. http://dx.doi.org/10.1021/jp9617377.

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Ramabhadran, Raghunath O., et Krishnan Raghavachari. « Theoretical Thermochemistry for Organic Molecules : Development of the Generalized Connectivity-Based Hierarchy ». Journal of Chemical Theory and Computation 7, no 7 (24 juin 2011) : 2094–103. http://dx.doi.org/10.1021/ct200279q.

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Raghavachari, Krishnan, Boris B. Stefanov et Larry A. Curtiss. « Accurate thermochemistry for larger molecules : Gaussian-2 theory with bond separation energies ». Journal of Chemical Physics 106, no 16 (22 avril 1997) : 6764–67. http://dx.doi.org/10.1063/1.473659.

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Nagy, Balázs, Péter Szakács, József Csontos, Zoltán Rolik, Gyula Tasi et Mihály Kállay. « Correction to “High-Accuracy Theoretical Thermochemistry of Atmospherically Important Sulfur-Containing Molecules” ». Journal of Physical Chemistry A 117, no 24 (7 juin 2013) : 5220. http://dx.doi.org/10.1021/jp405361p.

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Ishikawa, Atsushi, Masahiro Kamata et Hiromi Nakai. « Quantum chemical approach for condensed-phase thermochemistry (IV) : Solubility of gaseous molecules ». Chemical Physics Letters 655-656 (juillet 2016) : 103–9. http://dx.doi.org/10.1016/j.cplett.2016.05.041.

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Smirnov, Alexander N., et Victor G. N. Solomonik. « SPECTROSCOPIC AND THERMOCHEMICAL PROPERTIES OF ACTINIDE-CONTAINING SPECIES FROM FIRST PRINCIPLES : THORIUM AND AMERICIUM MONOXIDE MOLECULES ». IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 63, no 2 (8 février 2020) : 4–13. http://dx.doi.org/10.6060/ivkkt.20206302.6094.

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A relativistic version of a composite ab initio treatment of molecular spectroscopy and thermochemistry is developed, focusing on high-accuracy description of the properties of actinide (An) containing species. It is based on combining the calculation results at levels of theory with sufficiently full account of electron correlation, e.g., at the CCSDT(Q) level, but tackling only scalar relativity, with those obtained from more rigorous four-component relativistic calculations with the Dirac–Coulomb Hamiltonian. High accuracy achievable via this approach is revealed taking the examples of thorium and americium monoxide molecules. The errors in ab initio values for the bond length re, vibrational frequency ωe, and atomization energy D0 of the ThO molecule did not exceed 0.001 Å, 2.5 cm–1, and 0.5 kcal/mol, respectively. The composite numerical values for the first ionization potentials of the AmO molecule and the Am atom deviate from the experimental data just by 0.03 eV and 1 cm–1, respectively. For the first time, the proposed approach enabled high-accuracy evaluation of the molecular constants re, ωe and D0 for AmO and AmO+, as well as the second and third ionization potentials of the Am atom. The calculation results are indicative of a minor actinide contraction of the An–O bonds on going through the molecular series ThO → UO → AmO: the bond length in AmO is by 0.0073 Å shorter than that in ThO. The re(An–O) value is shown to be linearly dependent on the actinide atomic number in the periodic table. The results obtained may be used as benchmarks for parametrizing and calibrating the DFT functionals designed for treating An-containing molecules.
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19

Navrotsky, Alexandra. « Thermochemistry of New, Technologically Important Inorganic Materials ». MRS Bulletin 22, no 5 (mai 1997) : 35–41. http://dx.doi.org/10.1557/s0883769400033182.

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The past decade has seen exciting advances in the discovery, improved synthesis and processing, and molecular level engineering of new inorganic materials having specialized electronic, ceramic, and structural applications. Many such materials share two common characteristics: They are complex in structure and composition (think for example of oxide superconductors), and they must be prepared by a series of steps under carefully controlled conditions (consider the intricacies of zeolite synthesis for example). The use of low-temperature aqueous synthesis conditions, with appropriate attention to pH, inorganic and organic structure-directing agents, and subsequent drying and calcination protocols has led to a wealth of new and often metastable crystalline polymorphs, to amorphous materials, and to fine powders with particles of nanoscale dimensions. Methods such as sol-gel synthesis, chimie douce (soft chemistry), hydrothermal synthesis, chemical vapor deposition, and various beam-deposition and epitaxy techniques produce a wealth of materials not constrained to be in chemical equilibrium with their surroundings and not representing the state of lowest free energy. Modern materials chemists almost have their pet Maxwell Demon to select atoms at will and cause them to assemble in a structure of controllable dimensions. The wealth of possible new structures formed begins to mimic the riches of organic chemistry. In this field, the fact that all complex organic and biochemical molecules are metastable under ambient conditions with respect to a mixture of carbon dioxide, water, and other simple gases is irrelevant except in a conflagration.Liberation of ceramic science from the tyranny of high-temperature equilibrium is thus leading to new materials synthesized more quickly, at lower cost, and under environmentally more friendly conditions. There is of course a price to pay. First the synthetic procedures are more complex than traditional “mix, grind, fire, and repeat” ceramic processing. Second and more importantly, very little is known about the long-term stability of the materials formed, about their degradation during use, and about materials compatibility. Two examples of such problems are the potential corrosion of high Tc YBCO superconductors by ambient H2O and CO2, and the collapse to inactive phases of complex zeolitic and mesoporous catalysts under operating conditions. Chemical reactions in metastable materials are governed by an intertwined combination of thermodynamic driving forces and kinetic rates. For this rich landscape of new materials, neither the depths of the valleys nor the heights of the mountains are known. Often one cannot even tell which way is energetically downhill.
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20

Bennett, L. K. Rogers, D. W. Rogers et A. A. Zavitsas. « HELICAL STRUCTURE OF POLYUNSATURATED FATTY ACIDS : GAUSSIAN G4 THERMODYNAMIC FUNCTIONS ». SDRP Journal of Computational Chemistry & ; Molecular Modeling 5, no 1 (2021) : 543–49. http://dx.doi.org/10.25177/jccmm.5.1.ra.10739.

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Molecular modeling of lipids has been hampered by the size of these complex, biologically important molecules. Yet, understanding the structure and energy (enthalpy) of large molecules is critical to identifying their function in chemical equilibrium and transition state theory. In this work, we use both experimental data and G4 computed results, to show that cis polyunsaturated lipids have helical conformers. We present linear functions for the enthalpy of formation ΔfH°298 and the Gibbs free energy of formation ΔfG°298 as a function of n, where n is the number of carbon atoms in a linear carboxylic acid chain. Taking ΔfH°298 of a saturated acid as a starting point, we add the enthalpy of hydrogenation ΔhydH°298 at appropriate locations on the carbon chain to model polyunsaturated fatty acids. For example, taking eicosanoic acid (C20) as a saturated starting point, we add four enthalpies of cis-dehydrogenation (ΔhydH°298) to obtain arachidonic acid (eicosa-5Z,8Z,11Z,14Z-tetraenoic acid). We compare Gaussian-4 computational results, to show evidence of helical structure. We conclude that fatty acids can have helical conformers facilitating a broad range of biological functions. Keywords: G4 Calculations, Helix, Lipid, Molecular Structure, Thermochemistry
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Pilling, S., G. A. Carvalho, H. A. de Abreu, B. R. L. Galvão, C. H. da Silveira et M. S. Mateus. « Understanding the Molecular Kinetics and Chemical Equilibrium Phase of Frozen CO during Bombardment by Cosmic Rays by Employing the PROCODA Code ». Astrophysical Journal 952, no 1 (1 juillet 2023) : 17. http://dx.doi.org/10.3847/1538-4357/acdb4a.

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Abstract Within the cold regions of space, ices that are enriched with carbon monoxide (CO) molecules are exposed to ionizing radiation, which triggers new reactions and desorption processes. Laboratory studies on astrochemical ices employing different projectiles have revealed the appearance of several new species. In this study, we employed the upgraded PROCODA code, which involves a calculation phase utilizing thermochemistry data, to map the chemical evolution of pure CO ice irradiated by cosmic-ray analogs. In the model, we have considered 18 different chemical species (six observed: CO, CO2, C3, O3, C2O, and C5O3; 12 unobserved: C, O, C2, O2, CO3, C3O, C4O, C5O, C2O2, C2O3, C3O2, and C4O2) coupled at 156 reaction routes. Our best-fit model provides effective reaction rates (effective rate constants, (ERCs)), branching ratios for reactions within reaction groups, several desorption parameters, and the characterization of molecular abundances at the chemical equilibrium (CE) phase. The most abundant species within the ice at the CE phase were atomic oxygen (68.2%) and atomic carbon (18.2%), followed by CO (11.8%) and CO2 (1.6%). The averaged modeled desorption yield and rate were 1.3e5 molecules ion−1 and 7.4e13 molecules s−1, respectively, while the average value of ERCs in the radiation-induced dissociation reactions was 2.4e-1 s−1 and for the bimolecular reactions it was 4.4e-24 cm3 molecule−1 s−1. We believe that the current kinetics study can be used in future astrochemical models to better understand the chemical evolution of embedded species within astrophysical ices under the presence of an ionizing radiation field.
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Allendorf, Mark D., et Carl F. Melius. « Theoretical study of thermochemistry of molecules in the silicon-carbon-chlorine-hydrogn system ». Journal of Physical Chemistry 97, no 3 (janvier 1993) : 720–28. http://dx.doi.org/10.1021/j100105a031.

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Allendorf, Mark D., et Carl F. Melius. « Theoretical study of the thermochemistry of molecules in the silicon-carbon-hydrogen system ». Journal of Physical Chemistry 96, no 1 (janvier 1992) : 428–37. http://dx.doi.org/10.1021/j100180a080.

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Allendorf, Mark D., Carl F. Melius, Pauline Ho et Michael R. Zachariah. « Theoretical Study of the Thermochemistry of Molecules in the Si-O-H System ». Journal of Physical Chemistry 99, no 41 (octobre 1995) : 15285–93. http://dx.doi.org/10.1021/j100041a052.

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Motalov, V. B., A. M. Dunaev, L. S. Kudin, M. F. Butman et K. W. Krämer. « Molecular and ionic sublimation of neodymium, dysprosium, holmium, and erbium triiodides and thermochemistry of molecules and ions ». International Journal of Mass Spectrometry 457 (novembre 2020) : 116431. http://dx.doi.org/10.1016/j.ijms.2020.116431.

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Abdel-Halim, Hamzeh M., et Sawsan M. Jaafreh. « Reaction Rate Constants from Classical Trajectories of Atom-Diatomic Molecule Collisions ». Zeitschrift für Naturforschung A 63, no 3-4 (1 avril 2008) : 159–69. http://dx.doi.org/10.1515/zna-2008-3-408.

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Classical trajectory calculations for various atom-diatomic molecules were preformed using the three-dimensional Monte Carlo method. The reaction probabilities, cross-sections and rate constants of several systems were calculated. Equations of motion, which predict the positions and momenta of the colliding particles after each step, have been integrated numerically by the Runge-Kutta-Gill and Adams-Moulton methods. Morse potential energy surfaces were used to describe the interaction between the atom and each atom in the diatomic molecules. The results were compared with experimental ones and with other theoretical values. Good agreement was obtained between calculated rate constants and those obtained experimentally. Also, reasonable agreement was observed with theoretical rate constants obtained by other investigators using different calculation methods. The effects of the temperature, the nature of the colliding particles and the thermochemistry were studied. The results showed a strong dependence of the reaction rates on these factors.
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Gheorghe, Daniela, Ana Neacsu et Stefan Perisanu. « Thermochemistry of Eight Membered Ring Hydrocarbons. The Enthalpy of Formation of Cyclooctane ». Revista de Chimie 71, no 3 (1 janvier 2001) : 507–15. http://dx.doi.org/10.37358/rc.20.3.8025.

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A new value of the enthalpy of formation of cyclooctane (-156.2�1.2 kJ mol-1) based on heat of combustion measurements is reported. Its solid - liquid phase change was investigated by differential scanning calorimetry in both directions revealing an overcooling effect of over 23 K. Our enthalpy of formation of cyclooctane was used together with literature values of heats of hydrogenation of 8 carbon atoms cycloolefins to calculate the enthalpies of formation of the later. The strain energies of the investigated molecules were calculated and discussed.
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Pople, John A., Brian T. Luke, Michael J. Frisch et J. Stephen Binkley. « Theoretical thermochemistry. 1. Heats of formation of neutral AHn molecules (A = Li to Cl) ». Journal of Physical Chemistry 89, no 11 (mai 1985) : 2198–203. http://dx.doi.org/10.1021/j100257a013.

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Ho, Pauline, et Carl F. Melius. « Theoretical Study of the Thermochemistry of Molecules in the Si-O-H-C System ». Journal of Physical Chemistry 99, no 7 (février 1995) : 2166–76. http://dx.doi.org/10.1021/j100007a056.

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Melius, Carl F., et Pauline Ho. « Theoretical study of the thermochemistry of molecules in the silicon-nitrogen-hydrogen-fluorine system ». Journal of Physical Chemistry 95, no 3 (février 1991) : 1410–19. http://dx.doi.org/10.1021/j100156a070.

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Ho, Pauline, Michael E. Colvin et Carl F. Melius. « Theoretical Study of the Thermochemistry of Molecules in the Si−B−H−Cl System ». Journal of Physical Chemistry A 101, no 49 (décembre 1997) : 9470–88. http://dx.doi.org/10.1021/jp971947z.

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Martin, Jan M. L., Peter R. Taylor, J. P. François et R. Gijbels. « Ab initio study of the spectroscopy and thermochemistry of the C2N and CN2 molecules ». Chemical Physics Letters 226, no 5-6 (août 1994) : 475–83. http://dx.doi.org/10.1016/0009-2614(94)00758-6.

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33

Petrie, Simon. « Circumstellar Calcium Chemistry ». Australian Journal of Chemistry 57, no 1 (2004) : 67. http://dx.doi.org/10.1071/ch03173.

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High-level ab initio calculations are used to explore several aspects of calcium chemistry of direct relevance to formation and reaction of calcium-containing molecules in circumstellar envelopes. Counterpoise-corrected G2 and G2(MP2) calculations have been used to determine the bond dissociation energies (BDEs) of Ca+/NC2n+1H complexes (n = 0, 1, 2); these complexes, and CaNC7H+, are also assessed through counterpoise-corrected MP2(thaw)/6-311 + G(3df,2p) calculations. The relative energies of isomers of the feasible Ca(CN), Ca(C3N), and Ca(C5N) products (which may arise from dissociative recombination of the Ca+/NC2n+1H complexes) are obtained from G2 and G2(MP2) calculations; these calculations also permit evaluation of the thermochemistry of the dissociative recombination reactions in question. Thermochemical data are presented for a possible loss mechanism for calcium-containing neutrals by reaction with molecular ions in circumstellar envelopes. Finally, we provide an empirical assessment of the prospects for detecting the Ca(CN), Ca(C3N), and Ca(C5N) radicals within circumstellar environments.
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Charaya, Sumit, et Joseph W. Bozzelli. « Thermochemistry, Bond Energies and Internal Rotor Potentials of Acetic Acid Hydrazide, Acetamide, N-Methyl Acetamide (NMA) and Radicals ». Thermo 1, no 1 (2 mars 2021) : 15–31. http://dx.doi.org/10.3390/thermo1010002.

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Structures, thermochemical properties, bond energies, and internal rotation potentials of acetic acid hydrazide (CH3CONHNH2), acetamide (CH3CONH2), and N-methyl acetamide (CH3CONHCH3), and their radicals corresponding to the loss of hydrogen atom, have been studied. Gas-phase standard enthalpies of formation and bond energies were calculated using the DFT methods B3LYP/6-31G(d,p), B3LYP/6-31G(2d,2p) and the composite CBS-QB3 methods employing a series of work reactions further to improve the accuracy of the ΔHf°(298 K). Molecular structures, vibration frequencies, and internal rotor potentials were calculated at the DFT level. The parent molecules’ standard formation enthalpies of CH3–C=ONHNH2, CH3–C=ONH2, and CH3–C=ONHCH3 were evaluated as −27.08, −57.40, and −56.48 kcal mol−1, respectively, from the CBS–QB3 calculations. Structures, internal rotor potentials, and C–H and N–H bond dissociation energies are reported. The DFT and the CBS-QB3 enthalpy values show close agreement, and this accord is attributed to the use of isodesmic work reactions for the analysis. The agreement also suggests this combination of the B3LYP/work reaction approach is acceptable for larger molecules. Internal rotor potentials for the amides are high, ranging from 16 to 22 kcal mol−1.
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GOLOVIN, A. V., D. A. PONOMAREV et V. V. TAKHISTOV. « THERMOCHEMISTRY OF ORGANIC, HETEROORGANIC, AND INORGANIC MOLECULES AND THEIR FRAGMENTS : "QUANTUM-CHEMICAL CALCULATIONS OF THERMOCHEMICAL PARAMETERS : MOLECULES AND THEIR FRAGMENTS" ». Journal of Theoretical and Computational Chemistry 09, supp01 (janvier 2010) : 125–53. http://dx.doi.org/10.1142/s0219633610005529.

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Analysis of theoretical enthalpies of formation for about 300 molecules and their fragments (free radicals, biradicals, and ions) was performed to show that the results of semiempirical, DFT, and ab initio methods must be taken with great caution. A brief review of the authors' alternative empirical methodologies for calculation of enthalpies of formation for molecules (enthalpic shift procedure) and free radicals (enthalpies of isodesmic reactions) is given.
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Ottonello, G., et M. Vetuschi Zuccolini. « Ab initio thermochemistry of some geochemically relevant molecules in the system Cr-O-H-Cl ». Geochimica et Cosmochimica Acta 69, no 14 (juillet 2005) : 3505–18. http://dx.doi.org/10.1016/j.gca.2005.02.012.

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37

Lago, A. F., et Tomas Baer. « Dissociation dynamics and thermochemistry of chloroform and tetrachloroethane molecules studied by threshold photoelectron photoion coincidence ». International Journal of Mass Spectrometry 252, no 1 (mai 2006) : 20–25. http://dx.doi.org/10.1016/j.ijms.2006.01.013.

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38

Ferrer, Maxime, Ibon Alkorta, José Elguero et Josep M. Oliva-Enrich. « Carboranes as Lewis Acids : Tetrel Bonding in CB11H11 Carbonium Ylide ». Crystals 11, no 4 (7 avril 2021) : 391. http://dx.doi.org/10.3390/cryst11040391.

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High-level quantum-chemical computations (G4MP2) are carried out in the study of complexes featuring tetrel bonding between the carbon atom in the carbenoid CB11H11—obtained by hydride removal in the C-H bond of the known closo-monocarbadodecaborate anion CB11H12(−) and acting as Lewis acid (LA)—and Lewis bases (LB) of different type; the electron donor groups in the tetrel bond feature carbon, nitrogen, oxygen, fluorine, silicon, phosphorus, sulfur, and chlorine atomic centres in neutral molecules as well as anions H(−), OH(−), and F(−). The empty radial 2pr vacant orbital on the carbon centre in CB11H11, which corresponds to the LUMO, acts as a Lewis acid or electron attractor, as shown by the molecular electrostatic potential (MEP) and electron localization function (ELF). The thermochemistry and topological analysis of the complexes {CB11H11:LB} are comprehensively analysed and classified according to shared or closed-shell interactions. ELF analysis shows that the tetrel C⋯X bond ranges from very polarised bonds, as in H11B11C:F(−) to very weak interactions as in H11B11C⋯FH and H11B11C⋯O=C=O.
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Izato, Yu-ichiro, Akira Matsugi, Mitsuo Koshi et Atsumi Miyake. « A simple heuristic approach to estimate the thermochemistry of condensed-phase molecules based on the polarizable continuum model ». Physical Chemistry Chemical Physics 21, no 35 (2019) : 18920–29. http://dx.doi.org/10.1039/c9cp03226f.

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Sieck, L. Wayne. « Thermochemistry of solvation of sulfur hexafluoride monoanion by simple polar organic molecules in the vapor phase ». Journal of Physical Chemistry 90, no 25 (décembre 1986) : 6684–87. http://dx.doi.org/10.1021/j100283a018.

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Gong, Liangfa, Qianshu Li, Wenguo Xu, Yaoming Xie et Henry F. Schaefer. « Novel Interhalogen Molecules : Structures, Thermochemistry, and Electron Affinities of Dibromine Fluorides Br2Fn/Br2Fn-(n= 1−6) ». Journal of Physical Chemistry A 108, no 16 (avril 2004) : 3598–614. http://dx.doi.org/10.1021/jp031311+.

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42

HO, P., M. E. COLVIN et C. F. MELIUS. « ChemInform Abstract : Theoretical Study of the Thermochemistry of Molecules in the Si-B-H-Cl System. » ChemInform 29, no 12 (23 juin 2010) : no. http://dx.doi.org/10.1002/chin.199812011.

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Holmes, John L., Karl J. Jobst et Johan K. Terlouw. « Small (Poly)Unsaturated Oxygen Containing Ions and Molecules : A Brief Assessment of Their Thermochemistry Based on Computational Chemistry ». European Journal of Mass Spectrometry 15, no 2 (avril 2009) : 261–73. http://dx.doi.org/10.1255/ejms.959.

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The CBS-QB3, CBS-APNO and Gaussian-3 model chemistries have been used to determine the ionic and neutral heats of formation and the adiabatic ionization energies ( IEa) derived therefrom, for the ca 30 principal isomers of the C3H2O•+ and the C4H4O•+ families of radical cations. Theory and experiment are in excellent agreement for those molecules whose experimental IEa has been accurately measured. In contrast, large deviations from the computed values were found for a great many ionic heats of formation reported in the literature. These deviations largely arise from the uncertainty in the heat of formation of the corresponding neutral species for which often only a rough estimate is available. A useful by-product of this study is that it permits the evaluation of new Benson-type group additivity ( GA) terms appropriate for highly unsaturated oxygen containing molecules. Several new GA terms are proposed but it is also argued that a single GA term for the ketene function cannot be defined.
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Allendorf, Mark D., et Carl F. Melius. « Thermochemistry of Molecules in the B−N−Cl−H System : Ab InitioPredictions Using the BAC-MP4 Method ». Journal of Physical Chemistry A 101, no 14 (avril 1997) : 2670–80. http://dx.doi.org/10.1021/jp962905y.

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Micca Longo, G., V. Piccinni et S. Longo. « Evaluation of CaSO4 micrograins in the context of organic matter delivery : thermochemistry and atmospheric entry ». International Journal of Astrobiology 18, no 4 (23 juillet 2018) : 345–52. http://dx.doi.org/10.1017/s1473550418000204.

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AbstractIn this paper, anhydrous calcium sulphate CaSO4 (anhydrite) is considered as a carrier material for organic matter delivery from Space to Earth. Its capability of incorporating important fractions of water, leading to different species like bassanite and gypsum, as well as organic molecules; its discovery on Mars surface and in meteorites; the capability to dissipate much energy by its chemical decomposition into solid (CaO) and gaseous (SO3) oxide, make anhydrite a very promising material in an astrobiological perspective. Since chemical cooling has been recently considered by some of the present authors for the case of Ca/Mg carbonates, CaSO4 can be placed into a class of ‘white soft minerals’ (WSM) of astrobiological interest. In this context, CaSO4 is evaluated here by using the atmospheric entry model previously developed for carbonates. The model includes grain dynamics, thermochemistry, stoichiometry, radiation and evaporation heat losses. Results are discussed in comparison with MgCO3 and CaCO3 and show that sub-mm anhydrite grains are potentially effective organic matter carriers. A Monte Carlo simulation is used to provide distributions of the sulphate fraction as a function of altitude. Two-zone model results are presented to support the isothermal grain hypothesis.
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Khan, Shumaila S., Xinrui Yu, Jeffrey R. Wade, R. Dean Malmgren et Linda J. Broadbelt. « Thermochemistry of Radicals and Molecules Relevant to Atmospheric Chemistry : Determination of Group Additivity Values using G3//B3LYP Theory ». Journal of Physical Chemistry A 113, no 17 (30 avril 2009) : 5176–94. http://dx.doi.org/10.1021/jp809361y.

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Ishikawa, Atsushi, et Hiromi Nakai. « Quantum chemical approach for condensed-phase thermochemistry (II) : Applications to formation and combustion reactions of liquid organic molecules ». Chemical Physics Letters 624 (mars 2015) : 6–11. http://dx.doi.org/10.1016/j.cplett.2015.01.054.

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Szidarovszky, Tamás, et Attila G. Császár. « Toward accurate thermochemistry of the 24MgH, 25MgH, and 26MgH molecules at elevated temperatures : Corrections due to unbound states ». Journal of Chemical Physics 142, no 1 (7 janvier 2015) : 014103. http://dx.doi.org/10.1063/1.4904858.

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49

CHEETHAM, A. K., et J. D. GALE. « ChemInform Abstract : Computer Simulations of the Structure, Thermochemistry and Dynamics of Adsorbed Molecules in Zeolite and Related Catalysts ». ChemInform 24, no 27 (20 août 2010) : no. http://dx.doi.org/10.1002/chin.199327324.

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Sabbah, Raphaël, et Meriem Gouali. « Energétique des liaisons inter et intramoléculaires dans les trois isomères de l'aminophénol ». Canadian Journal of Chemistry 74, no 4 (1 avril 1996) : 500–507. http://dx.doi.org/10.1139/v96-054.

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The prsesent work is concerned with a thermodynamic study of the three aminophenol isomers (general formula: C6H7NO). It was achieved using four techniques: combustion calorimetry of small amounts of substance (a few milligrams), sublimation calorimetry, differential thermal analysis, and heat capacity measurements. From this study, it was possible: to determine the enthalpies of combustion, sublimation, and fusion of these compounds; to discuss the relative stability of the three molecules; to determine the intermolecular enthalpy bonds; to determine the experimental resonance energies and to compare them with the theoretical values; to determine the atomization enthalpies and to compare them with the values calculated from the energetical contributions previously determined in our laboratory; to consider the existence of an intramolecular hydrogen bond in the ortho isomer. Key words: thermodynamics; thermochemistry; calorimetry; differential thermal analysis; 2-aminophenol or ortho-aminophenol; 3-aminophenol or meta-aminophenol; 4-aminophenol or para-aminophenol; enthalpy of combustion, of sublimation, of fusion, of atomization, enthalpy of inter and intramolecular bonds; hydrogen bond; resonance energy; triple point temperature.
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