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Journal articles on the topic 'Bond enthalpy'

Author: Grafiati

Published: 7 June 2025

Last updated: 2 August 2025

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1

Tsioptsias, Costas. "Thermodynamic and Vibrational Aspects of Peptide Bond Hydrolysis and Their Potential Relationship to the Harmfulness of Infrared Radiation." Molecules 28, no. 23 (2023): 7902. http://dx.doi.org/10.3390/molecules28237902.

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The primary physicochemical effect upon exposure to infrared radiation (IR) is the temperature increase of cells. The degradation of proteins via the hydrolysis of peptide bonds is related to cell malfunction. In this work, the degradation of proteins/peptides under the influence of IR radiation is theoretically studied. It is shown that the low value of enthalpy of peptide bond hydrolysis has two consequences: (a) the enthalpy of hydrolysis is sensitive to small variations in the bond strength, and the hydrolysis of weak peptide bonds is exothermic, while the hydrolysis of stronger bonds is e

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2

Garipelli, Nagaraju, RB Sunoj, Madhava Reddy B, Jithan AV, and Chinnalaliah Runja. "Quantification of Intramolecular Hydrogen Bond in Neurotransmitter Dopamine." International Journal of Pharmaceutical Sciences and Nanotechnology 2, no. 3 (2009): 671–74. http://dx.doi.org/10.37285/ijpsn.2009.2.3.12.

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Dopamine is a catecholamine chemically, 3, 4-dihydroxyphenyethylamine. It has intramolecular H-bond (IHB) between the two hydroxyl groups. The energy of intramolecular H-bond might contribute energy in binding of the neurotransmitter with the receptors. Here the IHB in Dopamine is calculated in different levels of theories. The energetics of intramolecular hydrogen bonds is of fundamental importance in biochemistry. In contrast with intermolecular H-bonds, whose enthalpy can be determined by a supermolecular approach, there is no general accepted procedure to determine the enthalpy of an intra

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3

Bartmess, John E., and Robert J. Hinde. "The gas-phase acidities of the elemental hydrides are functions of electronegativity and bond length." Canadian Journal of Chemistry 83, no. 11 (2005): 2005–12. http://dx.doi.org/10.1139/v05-218.

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The gas-phase Brønsted acidities of the group 1, group 2, and main group elemental hydrides (XHn) are shown to be a combined function of the bond length, electronegativity, and position in the periodic table, via a separation of the acidity into coulombic and electronic reorganization enthalpy parts. The Coulombic acidity is defined as the enthalpy to separate unit positive and negative charges from the neutral acid's XH bond length to infinity; the reorganization enthalpy is the difference between that and the measured acidity, and represents the enthalpy required to reorganize the electrons

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4

Papina, T. S., V. P. Kolesov, V. A. Lukyanova, O. V. Boltalina, A. Yu Lukonin, and L. N. Sidorov. "Enthalpy of Formation and C−F Bond Enthalpy of Fluorofullerene C60F36." Journal of Physical Chemistry B 104, no. 23 (2000): 5403–5. http://dx.doi.org/10.1021/jp000409a.

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5

Vdovenko, Sergei, Igor Gerus, Elena Fedorenko та Valery Kukhar. "C–H⋯F Hydrogen Bond and Integral Intensities of Vinyl C–H Vibtations in Push-Pull β-Dimethylaminotrifluoromethyl Ketone and Its Deuterated Analog". ISRN Spectroscopy 2013 (17 січня 2013): 1–13. http://dx.doi.org/10.1155/2013/640896.

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The accurate analysis of infrared spectra (both wavenumbers and intensities) of (E)-4-(dimethylamino)-1,1,1-trifluorobut-3-en-2-one (DMTBN) and (E)-4-(hexadeutero-dimethylamino)-1,1,1-trifluorobut-3-en-2-one (d6-DMTBN) revealed that besides intramolecular hydrogen bond in the (EE) conformer, these enaminoketones form cyclic dimers between the (EZ) and (EE) conformers due to intermolecular hydrogen bonds, namely, O=C and . Evaluation of constant and enthalpy of formation of these H-bonds revealed that O=C bond has greater and more negative than bond (cf. 214.4 M−1, −21.7 kJ M−1dm3, and 16.4 M−1

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6

Sabbah, Raphaël, and Meriem Gouali. "Energétique des liaisons inter et intramoléculaires dans les trois isomères de l'aminophénol." Canadian Journal of Chemistry 74, no. 4 (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

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7

Wang, Kaiming, Dong Du, Baohua Chang, et al. "Mechanical Properties, Electronic Structures, and Debye Temperature of NixBy Compounds Obtained by the First Principles Calculations." Crystals 8, no. 12 (2018): 451. http://dx.doi.org/10.3390/cryst8120451.

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Mechanical properties, electronic properties, and Debye temperatures of NixBy (Ni3B, Ni2B, Ni4B3 and NiB) compounds were obtained by the first principles calculations based on the density functional theory (DFT). The results showed that the formation enthalpy of the NixBy compounds were stable with negative formation enthalpy. NiB had the largest B, G, and E, and the smallest υ; it also had the highest hardness (10.8 GPa) and Debye temperature (681.8 K). Ni4B3 had the strongest anisotropy. It was found that the valence bonds of the NixBy compounds studied were composed of both metal bond and c

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8

Pimenova, Svetlana M., Svetlana V. Melkhanova, Victor P. Kolesov, and Anatolii S. Lobach. "The Enthalpy of Formation and C−H Bond Enthalpy of Hydrofullerene C60H36." Journal of Physical Chemistry B 106, no. 9 (2002): 2127–30. http://dx.doi.org/10.1021/jp012258x.

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9

Robson, Fernandes de Farias. "An unusual approach to the bond enthalpy in hydrogen molecule: the contribution of relativistic effects." Chemistry Research Journal 1, no. 5 (2016): 9–10. https://doi.org/10.5281/zenodo.13969996.

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In the present work, the H-H bond enthalpy in hydrogen molecule explained/calculated by using the Bohr atom approach, as well as Slater rules and taking into account relativistic effects. It is shown that in the hydrogen molecule, the electron moves at 0.7155 c, with a relativistic mass of 13.04 x 10<sup>-31 </sup>kg and that the most part of the H-H bond enthalpy are related with the change in potential energy in individual H atoms.

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10

Mahmood, Asif, Muhammad Saqib, Muhammad Ali, Muhammad Imran Abdullah, and Bilal Khalid. "Theoretical investigation for the designing of novel antioxidants." Canadian Journal of Chemistry 91, no. 2 (2013): 126–30. http://dx.doi.org/10.1139/cjc-2012-0356.

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In this study, the antioxidant potential of salicylic acid and its derivatives was determined. O–H bond dissociation enthalpy ionization potential and spin densities were computed, which are important characteristics of antioxidants. We have designed new antioxidants on the basis of information obtained from the results of this study and a literature review. O–H bond dissociation enthalpy, ionization potential, and spin densities of designed compounds were also calculated to analyze the effect of the size of the heterocyclic ring, the electronegativity of the heteroatom, the number of hydroxyl

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11

Tamafo Fouegue, Aymard Didier, Julius Numbonui Ghogomu, Désiré Bikélé Mama, Nyiang Kennet Nkungli, and Elie Younang. "Structural and Antioxidant Properties of Compounds Obtained from Fe2+Chelation by Juglone and Two of Its Derivatives: DFT, QTAIM, and NBO Studies." Bioinorganic Chemistry and Applications 2016 (2016): 1–13. http://dx.doi.org/10.1155/2016/8636409.

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The chelating ability of juglone and two of its derivatives towards Fe2+ion and the antioxidant activity (AOA) of the resulting chelates and complexes (in the presence of H2O and CH3OH as ligands) in gas phase is reported via bond dissociation enthalpy, ionization potential, proton dissociation enthalpy, proton affinity, and electron transfer enthalpy. The DFT/B3LYP level of theory associated with the 6-31+G(d,p) and 6-31G(d) Pople-style basis sets on the atoms of the ligands and the central Fe(II), respectively, was used. Negative chelation free energies obtained revealed that juglone derivat

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12

Poliak, Peter, and Adam Vagánek. "Torsional deformation effect on the N—H bond dissociation energy in diphenylamine." Acta Chimica Slovaca 6, no. 2 (2013): 182–86. http://dx.doi.org/10.2478/acs-2013-0029.

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Abstract In this work, the influence of the inter-ring dihedral angles and their deformation on the energetics of diphenylamine molecule and its radical is investigated by the B3LYP/6-311++G** approach. Our approximated bond dissociation enthalpy of diphenylamine is 370.0 kJ mol-1 and it is in good agreement with the recently published experimental data. The potential functions of both the molecule and the radical with respect to the mutual aromatic ring orientations are presented. The potential function for the molecule is of a double-barrier type, whereas the radical possesses a single-barri

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13

Medvedev, Alexander G., Andrei V. Churakov, Mger A. Navasardyan, Petr V. Prikhodchenko, Ovadia Lev, and Mikhail V. Vener. "Fast Quantum Approach for Evaluating the Energy of Non-Covalent Interactions in Molecular Crystals: The Case Study of Intermolecular H-Bonds in Crystalline Peroxosolvates." Molecules 27, no. 13 (2022): 4082. http://dx.doi.org/10.3390/molecules27134082.

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Energy/enthalpy of intermolecular hydrogen bonds (H-bonds) in crystals have been calculated in many papers. Most of the theoretical works used non-periodic models. Their applicability for describing intermolecular H-bonds in solids is not obvious since the crystal environment can strongly change H-bond geometry and energy in comparison with non-periodic models. Periodic DFT computations provide a reasonable description of a number of relevant properties of molecular crystals. However, these methods are quite cumbersome and time-consuming compared to non-periodic calculations. Here, we present

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14

Ogunyemi, Babatunde T. "Quantum chemical insights into the antioxidant mechanisms of luteolin and isorhamnetin: Elucidating structure-reactivity relationships, pharmacokinetics, and toxicity for therapeutic potential." Communication in Physical Sciences 12, no. 2 (2025): 1081–93. https://doi.org/10.4314/cps.v12i2.29.

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This study presents a comprehensive computational evaluation of the antioxidant properties, physicochemical characteristics, pharmacokinetics, and toxicity profiles of two naturally occurring flavonoids—luteolin and isorhamnetin. Using quantum chemical descriptors and density functional theory (DFT) at the B3LYP/6-31G(d,p) level, we assessed the bond dissociation enthalpy (BDE), adiabatic ionization potential (AIP), proton dissociation enthalpy (PDE), proton affinity (PA), and electron transfer enthalpy (ETE) of both compounds. Isorhamnetin demonstrated superior antioxidant potential, with low

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15

Pankratov, Alexei, and Alexei Shalabay. "Evaluation of the intramolecular hydrogen bond enthalpy by means of specialized quantum chemical methods." Journal of the Serbian Chemical Society 72, no. 2 (2007): 151–57. http://dx.doi.org/10.2298/jsc0702151p.

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By means of the MNDO/H, I-MNDO, MNDO/HB and MNDO/M methods, the values of the enthalpy of intramolecular hydrogen bond (IHB) formation for series of substances have been computed. The applicability of these methods for a semi-quantitative estimation of the IHB enthalpy in compounds with a planar quasicycle has been shown. .

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16

Surabhi, Divyamshu, and Nagamanju S. "Effect of the Position of the OH Functional Group on the Enthalpy of Combustion of Alcohols." Research & Reviews: Journal of Chemistry 10, no. 10 (2021): 8. https://doi.org/10.4172/2319-9849.10.10.001.

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Energy is one of the fundamental units that drive various processes. Among them, heat or thermal energy is quite abundant in nature; usually released outside the system as a byproduct. The total summation of internal energy stored within reactants or products is Enthalpy (H). The amount of heat lost or gained by a system is equal to the Change in enthalpy of combustion or ∆H. In the present study an attempt has been made to investigate whether the positioning of OH functional group in methanol, 2-propanol and 2-methylpropan-2-ol has any effect upon the standard enthalpy change. Calorimeter was

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17

Yang Zheng-Gang, Dou Er-Kang, Yang Yong, Li Tian-Rui, Zhang Xiao-Feng, and Wang Zhao-Dong. "First-principles studies on the impact of V or W doping on the mechanical properties of Mo<sub>2</sub>C." Acta Physica Sinica 74, no. 10 (2025): 0. https://doi.org/10.7498/aps.74.20250039.

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Secondary hardening ultra-high-strength steel is widely utilized in aerospace and other advanced engineering applications, with the nanoscale M<sub>2</sub>C precipitates serving as the primary strengthening factor. Mo plays a crucial role in the formation of the Mo<sub>2</sub>C secondary hardening phase, which can form composite M<sub>2</sub>C precipitates with elements such as Cr, V, and W, thereby modifying the composition and properties of Mo<sub>2</sub>C. To investigate the effects of V and W doping on Mo<sub>2</sub>C, this study

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18

Poła, Andrzej, Anna Palko-Łabuz, and Kamila Środa-Pomianek. "Theoretical Study of 2-(Trifluoromethyl)phenothiazine Derivatives with Two Hydroxyl Groups in the Side Chain-DFT and QTAIM Computations." Molecules 26, no. 17 (2021): 5242. http://dx.doi.org/10.3390/molecules26175242.

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Phenothiazines are known as synthetic antipsychotic drugs that exhibit a wide range of biological effects. Their properties result from the structure and variability of substituents in the heterocyclic system. It is known that different quantum chemical properties have a significant impact on drug behavior in the biological systems. Thus, due to the diversity in the chemical structure of phenothiazines as well as other drugs containing heterocyclic systems, quantum chemical calculations provide valuable methods in predicting their activity. In our study, DFT computations were applied to show s

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19

Bao, Junwei Lucas, Rubén Meana-Pañeda, and Donald G. Truhlar. "Multi-path variational transition state theory for chiral molecules: the site-dependent kinetics for abstraction of hydrogen from 2-butanol by hydroperoxyl radical, analysis of hydrogen bonding in the transition state, and dramatic temperature dependence of the activation energy." Chemical Science 6, no. 10 (2015): 5866–81. http://dx.doi.org/10.1039/c5sc01848j.

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20

Shaofeng, Li, and G. Pilcher. "Enthalpy of formation of pyridine-N-oxide: the dissociation enthalpy of the (NO) bond." Journal of Chemical Thermodynamics 20, no. 4 (1988): 463–65. http://dx.doi.org/10.1016/0021-9614(88)90184-x.

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21

Hosier, Christopher A., Ian D. Anderson, and Christopher J. Ackerson. "Acetylide-for-thiolate and thiolate-for-acetylide exchange on gold nanoclusters." Nanoscale 12, no. 11 (2020): 6239–42. http://dx.doi.org/10.1039/d0nr00869a.

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22

NAJAFI, MEYSAM, MOHAMMAD NAJAFI, and HOUSHANG NAJAFI. "THEORETICAL STUDY OF THE SUBSTITUENT EFFECTS ON THE REACTION ENTHALPIES OF THE ANTIOXIDANT MECHANISMS OF STOBADINE DERIVATIVES IN THE GAS-PHASE AND WATER." Journal of Theoretical and Computational Chemistry 12, no. 02 (2013): 1250116. http://dx.doi.org/10.1142/s0219633612501167.

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In this paper the reaction enthalpies of three antioxidant action mechanisms, HAT, SET–PT, and SPLET, for mono-substituted Stobadines were calculated in gas-phase and water. Results show that electron-withdrawing substituents increase the bond dissociation enthalpy (BDE), ionization potential (IP), and electron transfer enthalpy (ETE), while electron-donating ones cause a rise in the proton dissociation enthalpy (PDE) and proton affinity (PA). In comparison to gas-phase, water attenuates the substituent effect on all reaction enthalpies. Results show that IP and BDE values can be successfully

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23

Sabbah, Raphaël, and Lahcen El Watik. "Étude thermodynamique de l'acridone et de la thioxanthone." Canadian Journal of Chemistry 70, no. 1 (1992): 24–28. http://dx.doi.org/10.1139/v92-005.

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In the present work we studied acridone and thioxanthone by combustion calorimetry of small amounts of substance, by sublimation calorimetry, by differential thermal analysis, and by heat capacity measurements. The thermodynamic quantities derived are as follows: For acridone: [Formula: see text] [Formula: see text] [Formula: see text] [Formula: see text] For thioxanthone: [Formula: see text] [Formula: see text] [Formula: see text] [Formula: see text] ΔfusHm = (35.50 ± 0.28) kJ mol−1, Ttp = (487.88 ± 0.02) K. The experimental results permitted us to determine for each molecule its resonance en

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24

Yuan, Qiang, Tao Zhou, Lin Li, et al. "Hydrogen bond breaking of TPU upon heating: understanding from the viewpoints of molecular movements and enthalpy." RSC Advances 5, no. 39 (2015): 31153–65. http://dx.doi.org/10.1039/c5ra03984c.

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25

Rudenko, O. P., O. V. Saienko, R. O. Saienko, and O. S. Svechnikova. "Thermodynamic Parameters of the Viscous Flow in the Aqueous Solutions of Polyols." Ukrainian Journal of Physics 65, no. 9 (2020): 810. http://dx.doi.org/10.15407/ujpe65.9.810.

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Data experimentally obtained for the kinematic viscosity are used to calculate the thermodynamic characteristics of viscous flows in some polyols and their aqueous solutions. The solutions of glycerol, erythritol, xylitol, adonite, sorbitol, mannitol, and dulcite are studied, as well as the melts of erythritol, xylitol, and sorbitol. The entropy, enthalpy, and free energy of the viscous flow are calculated in the framework of the theory of reaction rate constants. A linear dependence between the true entropy and the enthalpy of the viscous flow in the researched systems is found, which allowed

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26

Zhang, Hong-Yu. "On the O–H bond dissociation enthalpy of catechol." New Journal of Chemistry 27, no. 3 (2003): 453–54. http://dx.doi.org/10.1039/b212161c.

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27

Airoldi, Claudio, and Maria R. M. C. Santos. "Calcium-oxygen bond enthalpy in hexakis(urea) calcium bromide." Journal of Chemical Thermodynamics 18, no. 3 (1986): 301–2. http://dx.doi.org/10.1016/0021-9614(86)90059-5.

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28

Xu, Shenying, Quan-De Wang, Mao-Mao Sun, Guoliang Yin, and Jinhu Liang. "Benchmark calculations for bond dissociation energies and enthalpy of formation of chlorinated and brominated polycyclic aromatic hydrocarbons." RSC Advances 11, no. 47 (2021): 29690–701. http://dx.doi.org/10.1039/d1ra05391d.

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Benchmark calculations using state-of-the-art DFT functionals and composite methods for bond dissociation energy and enthalpy of formation of halogenated polycyclic aromatic hydrocarbons are performed.

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29

Ngo, Chinh Thi. "THERMOCHEMICAL PARAMETERS OF ERGOTHIONEINE: A DFT STUDY USING M06, WB97XD AND TPSSTPSS METHODS." Vietnam Journal of Science and Technology 54, no. 2C (2018): 299. http://dx.doi.org/10.15625/2525-2518/54/2c/11850.

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Antioxidant properties of ergothioneine (ESH) have been investigated via hydrogen atomtransfer (HAT), single electron transfer-proton transfer (SET-PT) and sequential proton losselectron transfer (SPLET) mechanisms. Three new DFT methods including M06, WB97XD andTPSSTPSS at the 6-311++G(2df,2p) basis set were used to compute the thermochemicalparameters of ESH in the gas phase. Based on these methods, bond dissociation enthalpy (BDE),ionization energy (IE), proton dissociation enthalpy (PDE), proton affinity (PA) and electrontransfer enthalpy (ETE) were calculated. The results were also compar

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30

Dorofeeva, Olga V., and Oxana N. Ryzhova. "Enthalpy of Formation and O–H Bond Dissociation Enthalpy of Phenol: Inconsistency between Theory and Experiment." Journal of Physical Chemistry A 120, no. 15 (2016): 2471–79. http://dx.doi.org/10.1021/acs.jpca.6b02233.

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31

Inada, Y., Y. Tsutsui, H. Wasada, and S. Funahashi. "Solvation Structure of Solvated Cu(I) Ions in Non-Aqueous Solvents as Studied by EXAFS and ab initio Molecular Orbital Methods." Zeitschrift für Naturforschung B 54, no. 2 (1999): 193–99. http://dx.doi.org/10.1515/znb-1999-0207.

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The structure parameters around the Cu(I) ion in pyridine (PY), 4-methylpyridine (4MPY), 2-methylpyridine (2MPY), 2,6-dimethylpyridine (26DMPY), and acetonitrile (AN) were determined by the extended X-ray absorption fine structure (EXAFS) method. The solvation structures of the Cu(I) ion in PY, 4MPY, and AN are 4-coordinate tetrahedral with Cu-N bond lengths of 205, 205, and 200 pm, respectively. In the case of 2MPY and 26DMPY, the Cu(I) ion has a 3-coordinate triangular structure with a Cu-N bond length of 201 pm. Such a decrease in the coordination number was interpreted in terms of the bulk

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32

Vostrikov, Sergey V., Artemiy A. Samarov, Vladimir V. Turovtsev, Peter Wasserscheid, Karsten Müller, and Sergey P. Verevkin. "Thermodynamic Analysis of Chemical Hydrogen Storage: Energetics of Liquid Organic Hydrogen Carrier Systems Based on Methyl-Substituted Indoles." Materials 16, no. 7 (2023): 2924. http://dx.doi.org/10.3390/ma16072924.

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Liquid organic hydrogen carriers can store hydrogen in a safe and dense form through covalent bonds. Hydrogen uptake and release are realized by catalytic hydrogenation and dehydrogenation, respectively. Indoles have been demonstrated to be interesting candidates for this task. The enthalpy of reaction is a crucial parameter in this regard as it determines not only the heat demand for hydrogen release, but also the reaction equilibrium at given conditions. In this work, a combination of experimental measurements, quantum chemical methods and a group-additivity approach has been applied to obta

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33

Sabbah, Raphaël, and Laurence Perez. "Energétique des liaisons inter- et intramoléculaires dans les trois isomères du benzènediamine." Canadian Journal of Chemistry 75, no. 4 (1997): 357–64. http://dx.doi.org/10.1139/v97-041.

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The present work is concerned with a thermodynamic study of the three benzenediamine (BDA) isomers (general formula: C6H8N2). 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 as well as their triple point temperatures; to discuss the relative stability of the three molecules; to determine the experimental resonance energies and

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34

Feliciano, Inês O., Daniela P. Silva, M. Fátima M. Piedade, Carlos E. S. Bernardes, and Manuel E. Minas da Piedade. "First and Second Dissociation Enthalpies in Bi-Component Crystals Consisting of Maleic Acid and L-Phenylalanine." Molecules 26, no. 18 (2021): 5714. http://dx.doi.org/10.3390/molecules26185714.

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The energetics of the stepwise dissociation of a A:B2 bi-component crystal, according to A:B2(cr) → A:B(cr) + B(cr) and A:B(cr) → A(cr) + B(cr), was investigated using MA:Phe2 and MA:Phe (MA = maleic acid; Phe = L-phenylalanine) as model systems. The enthalpy changes associated with these sequential processes and with the overall dissociation reaction A:B2(cr) → A(cr) + 2B(cr) were determined by solution calorimetry. It was found that they are all positive, indicating that there is a lattice enthalpy gain when MA:Phe2 is formed, either from the individual precursors or by adding Phe to MA:Phe.

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35

Najafi, Meysam, and Syed Ali Raza Naqvi. "Theoretical study of the substituent effect on the hydrogen atom transfer mechanism of the irigenin derivatives antioxidant action." Journal of Theoretical and Computational Chemistry 13, no. 02 (2014): 1450010. http://dx.doi.org/10.1142/s0219633614500102.

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In this paper, 21 substituents with various electron donating and electron withdrawing characters were placed in available positions of irigenin in order to study their effect on the O – H bond dissociation enthalpy (BDE) via DFT/B3LYP method. Results indicated the substituents in X3 and X4 positions have exerted stronger influence upon BDE values of irigenin derivatives when compared with same substituents in X1 and X2 positions. The results show that intramolecular hydrogen bond effects are able to considerably stabilize the parents and radicals. The natural bond orbital (NBO) analysis resul

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36

Stephenson, W. Kirk, and Richard Fuchs. "Enthalpies of interaction of hydroxylic solutes with organic solvents." Canadian Journal of Chemistry 63, no. 9 (1985): 2535–39. http://dx.doi.org/10.1139/v85-419.

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Heats of solution of m-cresol, 1-butanol, 1-pentanol, t-amyl alcohol, and model compounds (toluene, ethyl ether, n-butyl methyl ether, t-butyl methyl ether) in 17 organic solvents (n-heptane, cyclohexane, carbon tetrachloride, 1,2-dichloroethane, α,α,α-trifluorotoluene, triethylamine, butyl ether, ethyl acetate, dimethylformamide, dimethyl sulfoxide, benzene, toluene, mesitylene, t-butyl alcohol, 1-octanol, methanol, 2,2,2-trifluoroethanol) have been combined with solute heats of vaporization to give solvation enthalpies (ΔH(v → S)). Dependencies of solute vs. model solvation enthalpy differen

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Azuxetullatif, Azuxetullatif. "Penentuan Aktivitas Antioksidan Mirisetin, Quersetin Dan Kaempferol Berdasarkan Metode Semiempiris Austin Model (AM 1)." Jurnal Penelitian Dan Pengkajian Ilmiah Eksakta 4, no. 1 (2025): 105–9. https://doi.org/10.47233/jppie.v4i1.1977.

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Research has been conducted on the determination of antioxidant activity using the parameters of Bond Dissociation Enthalpy (BDE), Single Electron Transfer-Proton Transfer (SET-PT), Proton Affinity (PA), and Electron Transfer Enthalpy (ETE) of myricetin, quercetin, and kaempferol compounds. Furthermore, through the geometric stages using the AM1 semi-empirical method. The results obtained showed that myricetin compounds have better antioxidant activity compared to quercetin and kaempferol compounds by considering the results of high BDE values, low SET-PT, high PA, and low ETE.

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38

Da Silva, Manuel A. V. Ribeiro, M. Luisa C. C. H. Ferrão, and Arminda M. L. Magalhães. "Standard enthalpy of formation of tris(2,4-pentanedionato)cobalt(III): The mean (Co-O) bond-dissociation enthalpy." Thermochimica Acta 129, no. 2 (1988): 229–35. http://dx.doi.org/10.1016/0040-6031(88)87338-6.

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Ismoilov, I. R., E. S. Dodkhoev, R. A. Ismoilov, S. Z. Nazhmudinov, and A. B. Badalov. "The Study of Regularities of Changing Melting Enthalpy of Intermetallides of Magnesium–Lantanoids Systems Rich in Magnesium." Mining science and technology 4, no. 2 (2019): 111–21. http://dx.doi.org/10.17073/2500-0632-2019-2-111-121.

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Providing a reasonable forecast of the required properties of intermetallic compounds (hereinafter also referred as intermetallides or IM) is an important scientific and commercial problem, which may be solved by focusing scientific researches and permanent generation of knowledge in this field. To date, researches in chemistry and physics of IM have been developing empirically for a simple reason, due to the complexity of describing the relationship between the crystal structure and chemical bonds, and, therefore, between all the properties of IM. IM is mainly characterized by metal type of c

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40

Lucarini, Marco, Gian Franco Pedulli, and Marta Cipollone. "Bond Dissociation Enthalpy of .alpha.-Tocopherol and Other Phenolic Antioxidants." Journal of Organic Chemistry 59, no. 17 (1994): 5063–70. http://dx.doi.org/10.1021/jo00096a061.

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41

Pop, Raluca, Mariana Ştefănut, Adina Căta, Cristian Tănasie, and Mihai Medeleanu. "Ab initio study regarding the evaluation of the antioxidant character of cyanidin, delphinidin and malvidin." Open Chemistry 10, no. 1 (2012): 180–86. http://dx.doi.org/10.2478/s11532-011-0128-1.

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AbstractA theoretical study regarding the evaluation of the antioxidant character of three of the most wide-spread anthocyanidins (cyanidin, delphinidin and malvidin) was carried out at ab initio level. Different parameters (bond dissociation enthalpy, ionization potential, proton affinity, and electron transfer enthalpy) were computed for each OH group of the compounds in order to predict their antioxidant capacity. Several molecular descriptors based on frontier molecular orbital theory (hardness, electrophilicity, frontier charge density) were also calculated, as well as the atomic charges

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42

Le, Tien Dung. "COMPUTATIONAL STUDY OF MOLECULAR STRUCTURES AND ANTIOXIDANT MECHANISM OF OVOTHIOLS." Vietnam Journal of Science and Technology 54, no. 2C (2018): 328. http://dx.doi.org/10.15625/2525-2518/54/2c/11854.

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In this paper, the molecular structure and antioxidant activity of ovothiols (OSH) have beenstudied by using four DFT functionals, namely B3LYP, B3PW91, X3LYP, M06 with the basisset of 6-311++G(2df,2p). Two major antioxidant mechanisms, namely, hydrogen atom transfer(HAT) and stepwise electron transfer-proton transfer (SET-PT) have been investigated andapplied on three optimized conformations of ovothiols. Bond dissociation enthalpy (BDE),vertical ionization energy (IE), proton dissociation enthalpy (PDE), chemical potential (μ),chemical hardness (η) and global electrophilicity (ω), have been

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43

Mordekovitz, Y., S. Sagi, S. Barzilai, and S. Hayun. "Effect of Nd content on the energetics of H2O adsorption and defect structure in the Ce(1−x)NdxO(2−0.5x) system." Journal of Materials Chemistry A 8, no. 41 (2020): 21842–51. http://dx.doi.org/10.1039/d0ta04613b.

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44

Mic, Mihaela, Adrian Pîrnău, Călin G. Floare, et al. "Antioxidant Activity Evaluation and Assessment of the Binding Affinity to HSA of a New Catechol Hydrazinyl-Thiazole Derivative." Antioxidants 11, no. 7 (2022): 1245. http://dx.doi.org/10.3390/antiox11071245.

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Polyphenols have attained pronounced attention due to their ability to provide numerous health benefits and prevent several chronic diseases. In this study, we designed, synthesized and analyzed a water-soluble molecule presenting a good antioxidant activity, namely catechol hydrazinyl-thiazole (CHT). This molecule contains 3′,4′-dihydroxyphenyl and 2-hydrazinyl-4-methyl-thiazole moieties linked through a hydrazone group with very good antioxidant activity in the in vitro evaluations performed. A preliminary validation of the CHT developing hypothesis was performed evaluating in silico the bon

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Ivanova, Elena V., and Heidi M. Muchall. "Influence of the number of water molecules on the mechanism of N-sulfinylaniline hydrolysis." Canadian Journal of Chemistry 83, no. 9 (2005): 1588–96. http://dx.doi.org/10.1139/v05-171.

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The mechanism of the uncatalyzed hydrolysis of N-sulfinylaniline (Ph-N=S=O) has been studied with B3LYP/6-31+G(2d,2p) in the gas phase, with explicit treatment of water molecules. Hydrolysis involves water attack on sulfur, with a close to perpendicular alignment of a water molecule and the NSO plane in both prereaction complexes and transition states for the rate-determining step. Consequently, the distance of the weak S···O interaction, together with the efficiency of protonation of either nitrogen (attack across the N=S bond) or oxygen (attack across the S=O bond) atoms of the NSO group, de

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46

Bohn, Manfred A., and Thomas M. Klapötke. "DFT and G2MP2 Calculations of the N-N Bond Dissociation Enthalpies and Enthalpies of Formation of Hydrazine, Monomethylhydrazine and Symmetrical and Unsymmetrical Dimethylhydrazine." Zeitschrift für Naturforschung B 59, no. 2 (2004): 148–52. http://dx.doi.org/10.1515/znb-2004-0205.

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In a combined DFT (B3LYP) and G2MP2 theoretical study the following enthalpies of formation (ΔH°f) and bond dissociation enthalpies (BDE) for hydrazine, methylhydrazine (MMH), 1,1- dimethylhydrazine (UDMH) and 1,2-dimethylhydrazine (SDMH) were determined: BDE/kJ mol−1: N2H4, 278±4; MMH, 272±4; UDMH, 259±12; SDMH, 272±12. ΔH°f/kJ mol−1: N2H4, 95±6; MMH, 94±4; UDMH, 80±4; SDMH, 91±4. The bond enthalpy for the N-N bond in hydrazine amounts to BE (N-N, H2N−NH2) = 159±4 kJ mol−1.

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Simões, Ricardo G., Filipe Agapito, Hermínio P. Diogo, and Manuel E. Minas da Piedade. "Enthalpy of Formation of Anisole: Implications for the Controversy on the O–H Bond Dissociation Enthalpy in Phenol." Journal of Physical Chemistry A 118, no. 46 (2014): 11026–32. http://dx.doi.org/10.1021/jp507267f.

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I-Ting, Tsai, M. Merced Montero-Campillo, Ibon Alkorta, José Elguero, and Manuel Yáñez. "Large Stabilization Effects by Intramolecular Beryllium Bonds in Ortho-Benzene Derivatives." Molecules 26, no. 11 (2021): 3401. http://dx.doi.org/10.3390/molecules26113401.

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Intramolecular interactions are shown to be key for favoring a given structure in systems with a variety of conformers. In ortho-substituted benzene derivatives including a beryllium moiety, beryllium bonds provide very large stabilizations with respect to non-bound conformers and enthalpy differences above one hundred kJ·mol−1 are found in the most favorable cases, especially if the newly formed rings are five or six-membered heterocycles. These values are in general significantly larger than hydrogen bonds in 1,2-dihidroxybenzene. Conformers stabilized by a beryllium bond exhibit the typical

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49

Singh, Madan, Benedict Molibeli Taele, and Ghanshyam Patel. "Effect of Shape and Size on Curie Temperature, Debye Frequency, Melting Entropy and Enthalpy of Nanosolids." Oriental Journal of Chemistry 34, no. 5 (2018): 2282–91. http://dx.doi.org/10.13005/ojc/340508.

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The shape and size dependent melting thermodynamics of metallic nanoparticles are predicted by application of bond theory model, free of any adjustable parameter. Thermodynamic properties like Debye frequency, Curie temperature, melting entropy and enthalpy of Al, Sn, In, Cu, β-Fe and Fe3O4 for spherical and non spherical shapes nanoparticles with different size have been studied. In this model, the effects of relaxation factor for the low dimension solids are considered. The depression in Debye frequency, Curie temperature, melting entropy and enthalpy is predicted. The model predictions are

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Choi, Young Joong, Ho Yun Lee, Seohan Kim, and Pung Keun Song. "Controlled Lattice Thermal Conductivity of Transparent Conductive Oxide Thin Film via Localized Vibration of Doping Atoms." Nanomaterials 11, no. 9 (2021): 2363. http://dx.doi.org/10.3390/nano11092363.

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Amorphization using impurity doping is a promising approach to improve the thermoelectric properties of tin-doped indium oxide (ITO) thin films. However, an abnormal phenomenon has been observed where an excessive concentration of doped atoms increases the lattice thermal conductivity (κl). To elucidate this paradox, we propose two hypotheses: (1) metal hydroxide formation due to the low bond enthalpy energy of O and metal atoms and (2) localized vibration due to excessive impurity doping. To verify these hypotheses, we doped ZnO and CeO2, which have low and high bond enthalpies with oxygen, r

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