Journal articles: 'Transfer free energy'

1

Serafin, Joseph M. "Transfer Free Energy and the Hydrophobic Effect." Journal of Chemical Education 80, no. 10 (October 2003): 1194. http://dx.doi.org/10.1021/ed080p1194.

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2

Stoltzfus-Dueck, T., and B. Scott. "Momentum flux parasitic to free-energy transfer." Nuclear Fusion 57, no. 8 (July 12, 2017): 086036. http://dx.doi.org/10.1088/1741-4326/aa7289.

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3

Gopich, Irina V., and Attila Szabo. "Single-Macromolecule Fluorescence Resonance Energy Transfer and Free-Energy Profiles." Journal of Physical Chemistry B 107, no. 21 (May 2003): 5058–63. http://dx.doi.org/10.1021/jp027481o.

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4

Mills, Eric A., and Steven S. Plotkin. "Protein Transfer Free Energy Obeys Entropy-Enthalpy Compensation." Journal of Physical Chemistry B 119, no. 44 (October 26, 2015): 14130–44. http://dx.doi.org/10.1021/acs.jpcb.5b09219.

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5

Mills, Eric A., and Steven S. Plotkin. "Density Functional Theory for Protein Transfer Free Energy." Journal of Physical Chemistry B 117, no. 42 (August 14, 2013): 13278–90. http://dx.doi.org/10.1021/jp403600q.

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6

Laria, Daniel, Giovanni Ciccotti, Mauro Ferrario, and Raymond Kapral. "Activation free energy for proton transfer in solution." Chemical Physics 180, no. 2-3 (March 1994): 181–89. http://dx.doi.org/10.1016/0301-0104(93)00002-e.

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7

Becker, E. W. "Free energy transfer in the cell by Calcium." Naturwissenschaften 77, no. 4 (April 1990): 176–77. http://dx.doi.org/10.1007/bf01131160.

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8

Arnaut, Luis G., and Sebastião J. Formosinho. "Free-energy relationships in organic electron transfer reactions." Journal of Molecular Structure: THEOCHEM 233 (September 1991): 209–30. http://dx.doi.org/10.1016/0166-1280(91)85065-f.

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9

Wu, Joe Z., Solmaz Azimi, Sheenam Khuttan, Nanjie Deng, and Emilio Gallicchio. "Alchemical Transfer Approach to Absolute Binding Free Energy Estimation." Journal of Chemical Theory and Computation 17, no. 6 (May 13, 2021): 3309–19. http://dx.doi.org/10.1021/acs.jctc.1c00266.

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10

Pedersen, Hans M. "Exact geometrical theory of free-space radiative energy transfer." Journal of the Optical Society of America A 8, no. 1 (January 1, 1991): 176. http://dx.doi.org/10.1364/josaa.8.000176.

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11

Schwermann, Christian, and Nikos L. Doltsinis. "Exciton transfer free energy from Car–Parrinello molecular dynamics." Physical Chemistry Chemical Physics 22, no. 19 (2020): 10526–35. http://dx.doi.org/10.1039/c9cp06419b.

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Free energies profiles for exciton transfer processes are calculated within ab initio molecular dynamics by applying restraining potentials to the Wannier centres of molecular orbitals corresponding to an electron-hole pair.

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12

Malloum, Alhadji, and Jeanet Conradie. "Water-ammonia and water-acetonitrile proton transfer free energy." Journal of Molecular Liquids 318 (November 2020): 114300. http://dx.doi.org/10.1016/j.molliq.2020.114300.

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13

Seapy, Dave G., Javier Gonzalez, and Kimberly O. Cameron. "Photoinduced intramolecular electron transfer: free energy and rigidity effects." Journal of Photochemistry and Photobiology A: Chemistry 64, no. 1 (March 1992): 35–48. http://dx.doi.org/10.1016/1010-6030(92)85092-9.

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14

Bock, Lars V., Christian Blau, Gunnar F. Schröder, Niels Fischer, Holger Stark, Andrea C. Vaiana, and Helmut Grubmüller. "Transfer RNAs Store Conformational Free Energy in the Ribosome." Biophysical Journal 102, no. 3 (January 2012): 67a. http://dx.doi.org/10.1016/j.bpj.2011.11.395.

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15

Farrán, Angeles, and Kurt D. Deshayes. "Free Energy Dependence of Intermolecular Triplet Energy Transfer: Observation of the Inverted Region." Journal of Physical Chemistry 100, no. 9 (January 1996): 3305–7. http://dx.doi.org/10.1021/jp9531467.

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16

Stoltzfus-Dueck, T., W. A. Hornsby, and S. R. Grosshauser. "Gyrokinetic simulations of momentum flux parasitic to free-energy transfer." Physics of Plasmas 29, no. 3 (March 2022): 032515. http://dx.doi.org/10.1063/5.0080368.

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Ion Landau damping interacts with a portion of the E × B drift to cause a nondiffusive outward flux of co-current toroidal angular momentum. Quantitative evaluation of this momentum flux requires nonlinear simulations to determine fL, the fraction of fluctuation free energy that passes through ion Landau damping, in fully developed turbulence. Nonlinear gyrokinetic simulations with the GKW code confirm the presence of the systematic symmetry-breaking momentum flux. For simulations with adiabatic electrons, fL scales inversely with the ion temperature gradient, because only the ion curvature drift can transfer free energy to the electrostatic potential. Although kinetic electrons should, in principle, relax this restriction, the ion Landau damping measured in collisionless kinetic-electron simulations remained at low levels comparable with ion-curvature-drift transfer, except when magnetic shear [Formula: see text] was strong. A set of simulations scanning the electron pitch-angle scattering rate showed only a weak variation of fL with the electron collisionality. However, collisional-electron simulations with electron temperature greater than ion temperature unambiguously showed electron-curvature-drift transfer supporting ion Landau damping, leading to a corresponding enhancement of the symmetry-breaking momentum flux.

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17

Stranius, Kati, Rachel Jacobs, Eranda Maligaspe, Helge Lemmetyinen, Nikolai V. Tkachenko, Melvin E. Zandler, and Francis D'Souza. "Excitation transfer in metal-ligand coordinated free-base porphyrin-magnesium phthalocyanine and free-base porphyrin-magnesium naphthalocyanine dyads." Journal of Porphyrins and Phthalocyanines 14, no. 11 (November 2010): 948–61. http://dx.doi.org/10.1142/s1088424610002847.

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Singlet excitation transfer in self-assembled dyads formed via axial coordination of imidazole appended free-base tetraphenylporphyrin, H2PIm , to either a magnesium phthalocyanine, MgPc , or a magnesium naphthalocyanine, MgNc is investigated in non-coordinating solvents using spectroscopic (optical and mass), electrochemical, and time-resolved transient absorption techniques. The newly assembled dyads are fully characterized by spectroscopic, computational and electrochemical methods. The binding constants measured from optical absorption spectral data are found to be in the range of 103–104 M-1 for the 1:1 dyads suggesting fairly stable complex formation. However, the anticipated 2:1 complex for Mg coordination is not observed under the present solution conditions. Electrochemical and computational studies suggested that photoinduced electron transfer to be a thermodynamically unfavorable process when free-base porphyrin is excited in these dyads. However, selective excitation of H2PIm entity in these dyads resulted in rapid excitation transfer and the position of the imidazole linkage on the H2P entity seem to direct the overall efficiency of excited energy transfer. Kinetics of energy transfer is monitored by transient absorption measurements using pump-probe technique and is compared with the earlier reported H2PIm:ZnPc and H2PIm:ZnNc dyads. The time constants are in the order of 0.2–18 ps depending upon the type and relative orientation of the donor and acceptor entities of the dyad indicating ultrafast excitation transfer, and agree fairly well with theoretically estimated values assuming Förster energy transfer mechanism.

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18

Polasa, Adithya, Seyed Hamid Tabari, and Mahmoud Moradi. "Developing Efficient Transfer Free Energy Calculation Methods for Hydrophobicity Predictions." Biophysical Journal 120, no. 3 (February 2021): 115a. http://dx.doi.org/10.1016/j.bpj.2020.11.913.

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19

Tjong, Harianto, and Huan-Xiang Zhou. "Prediction of Protein Solubility from Calculation of Transfer Free Energy." Biophysical Journal 95, no. 6 (September 2008): 2601–9. http://dx.doi.org/10.1529/biophysj.107.127746.

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20

Malloum, Alhadji, and Jeanet Conradie. "Proton transfer free energy and enthalpy from water to methanol." Computational and Theoretical Chemistry 1199 (May 2021): 113189. http://dx.doi.org/10.1016/j.comptc.2021.113189.

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21

Parson, William W. "Reorganization Energies, Entropies, and Free Energy Surfaces for Electron Transfer." Journal of Physical Chemistry B 125, no. 29 (July 19, 2021): 7940–45. http://dx.doi.org/10.1021/acs.jpcb.1c01932.

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22

Pedersen, Hans M. "Exact geometrical theory of free-space radiative energy transfer: errata." Journal of the Optical Society of America A 8, no. 9 (September 1, 1991): 1518. http://dx.doi.org/10.1364/josaa.8.001518.

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23

Baldwin, R. L. "Properties of hydrophobic free energy found by gas-liquid transfer." Proceedings of the National Academy of Sciences 110, no. 5 (January 14, 2013): 1670–73. http://dx.doi.org/10.1073/pnas.1220825110.

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24

King, Gregory, and Arieh Warshel. "Investigation of the free energy functions for electron transfer reactions." Journal of Chemical Physics 93, no. 12 (December 15, 1990): 8682–92. http://dx.doi.org/10.1063/1.459255.

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25

Tian, Wei, Hammad Naveed, Meishan Lin, and Jie Liang. "GeTFEP: A general transfer free energy profile of transmembrane proteins." Protein Science 29, no. 2 (November 11, 2019): 469–79. http://dx.doi.org/10.1002/pro.3763.

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26

Kakiuchi, Takashi. "Free energy coupling of electron transfer and ion transfer in two-immiscible fluid systems." Electrochimica Acta 40, no. 18 (December 1995): 2999–3003. http://dx.doi.org/10.1016/0013-4686(95)00234-6.

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27

Sampaio, Renato N., Eric J. Piechota, Ludovic Troian-Gautier, Andrew B. Maurer, Ke Hu, Phil A. Schauer, Amber D. Blair, Curtis P. Berlinguette, and Gerald J. Meyer. "Kinetics teach that electronic coupling lowers the free-energy change that accompanies electron transfer." Proceedings of the National Academy of Sciences 115, no. 28 (June 25, 2018): 7248–53. http://dx.doi.org/10.1073/pnas.1722401115.

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Electron-transfer theories predict that an increase in the quantum-mechanical mixing (HDA) of electron donor and acceptor wavefunctions at the instant of electron transfer drives equilibrium constants toward unity. Kinetic and equilibrium studies of four acceptor–bridge–donor (A-B-D) compounds reported herein provide experimental validation of this prediction. The compounds have two redox-active groups that differ only by the orientation of the aromatic bridge: a phenyl–thiophene bridge (p) that supports strong electronic coupling of HDA > 1,000 cm−1; and a xylyl–thiophene bridge (x) that prevents planarization and decreases HDA < 100 cm−1 without a significant change in distance. Pulsed-light excitation allowed kinetic determination of the equilibrium constant, Keq. In agreement with theory, Keq(p) were closer to unity compared to Keq(x). A van’t Hoff analysis provided clear evidence of an adiabatic electron-transfer pathway for p-series and a nonadiabatic pathway for x-series. Collectively, the data show that the absolute magnitude of the thermodynamic driving force for electron transfers are decreased when adiabatic pathways are operative, a finding that should be taken into account in the design of hybrid materials for solar energy conversion.

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28

Vanston, C. R., G. J. Kearley, A. J. Edwards, T. A. Darwish, N. R. de Souza, A. J. Ramirez-Cuesta, and M. G. Gardiner. "The free-energy barrier to hydride transfer across a dipalladium complex." Faraday Discussions 177 (2015): 99–109. http://dx.doi.org/10.1039/c4fd00182f.

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We use density-functional theory molecular dynamics (DFT-MD) simulations to determine the hydride transfer coordinate between palladium centres of the crystallographically observed terminal hydride locations, Pd–Pd–H, originally postulated for the solution dynamics of the complex bis-NHC dipalladium hydride [{(MesIm)₂CH₂}₂Pd₂H][PF₆], and then calculate the free-energy along this coordinate. We estimate the transfer barrier-height to be about 20 kcal mol⁻¹ with a hydride transfer rate in the order of seconds at room temperature. We validate our DFT-MD modelling using inelastic neutron scattering which reveals anharmonicity of the hydride environment that is so pronounced that there is complete failure of the harmonic model for the hydride ligand. The simulations are extended to high temperature to bring the H-transfer to a rate that is accessible to the simulation technique.

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29

Tutel, Yusuf, Gökhan Sevinç, Betül Küçüköz, Elif Akhuseyin Yildiz, Ahmet Karatay, Fatih Mehmet Dumanoğulları, Halil Yılmaz, Mustafa Hayvali, and Ayhan Elmali. "Ultrafast Electron/Energy Transfer and Intersystem Crossing Mechanisms in BODIPY-Porphyrin Compounds." Processes 9, no. 2 (February 8, 2021): 312. http://dx.doi.org/10.3390/pr9020312.

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Meso-substituted borondipyrromethene (BODIPY)-porphyrin compounds that include free base porphyrin with two different numbers of BODIPY groups (BDP-TTP and 3BDP-TTP) were designed and synthesized to analyze intramolecular energy transfer mechanisms of meso-substituted BODIPY-porphyrin dyads and the effect of the different numbers of BODIPY groups connected to free-base porphyrin on the energy transfer mechanism. Absorption spectra of BODIPY-porphyrin conjugates showed wide absorption features in the visible region, and that is highly valuable to increase light-harvesting efficiency. Fluorescence spectra of the studied compounds proved that BODIPY emission intensity decreased upon the photoexcitation of the BODIPY core, due to the energy transfer from BODIPY unit to porphyrin. In addition, ultrafast pump-probe spectroscopy measurements indicated that the energy transfer of the 3BDP-TTP compound (about 3 ps) is faster than the BDP-TTP compound (about 22 ps). Since the BODIPY core directly binds to the porphyrin unit, rapid energy transfer was seen for both compounds. Thus, the energy transfer rate increased with an increasing number of BODIPY moiety connected to free-base porphyrin.

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30

Gomes, Laercio, Daniel Rhonehouse, Dan T. Nguyen, Jie Zong, Arturo Chavez-Pirson, and Stuart D. Jackson. "Energy transfer and energy level decay processes of Er3+ in water-free tellurite glass." Optical Materials 50 (December 2015): 268–74. http://dx.doi.org/10.1016/j.optmat.2015.11.007.

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31

Sigman, Michael E., and Gerhard L. Closs. "Free energy and structure dependence of intramolecular triplet energy transfer in organic model compounds." Journal of Physical Chemistry 95, no. 13 (June 1991): 5012–17. http://dx.doi.org/10.1021/j100166a022.

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32

Kleban, Peter, and Ingo Perchel. "Fully-Finite Two-Dimensional Critical Systems: Casimir Terms and Instabilities." International Journal of Modern Physics B 11, no. 01n02 (January 20, 1997): 133–39. http://dx.doi.org/10.1142/s0217979297000174.

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We review recent results for the universal part of the free energy of fully-finite two-dimensional regions at criticality. Their effect on the total free energy is considered. Including non-universal edge free energy terms leads to various Casimir instabilities toward elongation, sharp corners on the boundary, and other behavior. Universal features of certain matrix elements of the transfer matrix and corner transfer matrix are also obtained.

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33

Cieśliński, Janusz T., Slawomir Smolen, and Dorota Sawicka. "Free Convection Heat Transfer from Horizontal Cylinders." Energies 14, no. 3 (January 22, 2021): 559. http://dx.doi.org/10.3390/en14030559.

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The results of experimental investigation of free convection heat transfer in a rectangular container are presented. The ability of the commonly accepted correlation equations to reproduce present experimental data was tested as well. It was assumed that the examined geometry fulfils the requirement of no-interaction between heated cylinder and bounded surfaces. In order to check this assumption recently published correlation equations that jointly describe the dependence of the average Nusselt number on Rayleigh number and confinement ratios were examined. As a heat source served electrically heated horizontal tube immersed in an ambient fluid. Experiments were performed with pure ethylene glycol (EG), distilled water (W), and a mixture of EG and water at 50%/50% by volume. A set of empirical correlation equations for the prediction of Nu numbers for Rayleigh number range 3.6 × 104 < Ra < 9.2 × 105 or 3.6 × 105 < Raq < 14.8 × 106 and Pr number range 4.5 ≤ Pr ≤ 160 has been developed. The proposed correlation equations are based on two characteristic lengths, i.e., cylinder diameter and boundary layer length.

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34

Eisenhart, Thomas T., William C. Howland, and Jillian L. Dempsey. "Proton-Coupled Electron Transfer Reactions with Photometric Bases Reveal Free Energy Relationships for Proton Transfer." Journal of Physical Chemistry B 120, no. 32 (August 8, 2016): 7896–905. http://dx.doi.org/10.1021/acs.jpcb.6b04011.

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35

Deng, Hongping, Guojian Wang, Bangshang Zhu, Lijuan Zhu, Dali Wang, Yuanyuan Zhuang, and Xinyuan Zhu. "Label-Free DNA Detection through Energy Transfer of Conjugated Polymer Complexes." Acta Chimica Sinica 70, no. 24 (2012): 2507. http://dx.doi.org/10.6023/a12100740.

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36

Fecenko, Christine J., H. Holden Thorp, and Thomas J. Meyer. "The Role of Free Energy Change in Coupled Electron−Proton Transfer." Journal of the American Chemical Society 129, no. 49 (December 2007): 15098–99. http://dx.doi.org/10.1021/ja072558d.

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37

Jones, Austin L., and Kirk S. Schanze. "Free Energy Dependence of Photoinduced Electron Transfer in Octathiophene-Diimide Dyads." Journal of Physical Chemistry A 124, no. 1 (November 21, 2019): 21–29. http://dx.doi.org/10.1021/acs.jpca.9b08622.

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38

Benjamin, Ilan, and Yu I. Kharkats. "Reorganization free energy for electron transfer reactions at liquid/liquid interfaces." Electrochimica Acta 44, no. 1 (September 1998): 133–38. http://dx.doi.org/10.1016/s0013-4686(98)00161-3.

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39

Markin, Vladislav S., and Alexander G. Volkov. "The gibbs free energy of ion transfer between two immiscible liquids." Electrochimica Acta 34, no. 2 (February 1989): 93–107. http://dx.doi.org/10.1016/0013-4686(89)87072-0.

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40

Guo, Zhihui, Fan Yang, Lihong Zhang, and Xingwang Zheng. "Electrogenerated chemiluminescence energy transfer for the label-free detection of DNA." Sensors and Actuators B: Chemical 177 (February 2013): 316–21. http://dx.doi.org/10.1016/j.snb.2012.10.141.

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41

Lopez, Onel L. A., Samuel Montejo-Sanchez, Richard D. Souza, Constantinos B. Papadias, and Hirley Alves. "On CSI-Free Multiantenna Schemes for Massive RF Wireless Energy Transfer." IEEE Internet of Things Journal 8, no. 1 (January 1, 2021): 278–96. http://dx.doi.org/10.1109/jiot.2020.3003114.

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42

Fox, L. S., M. Kozik, J. R. Winkler, and H. B. Gray. "Gaussian Free-Energy Dependence of Electron-Transfer Rates in Iridium Complexes." Science 247, no. 4946 (March 2, 1990): 1069–71. http://dx.doi.org/10.1126/science.247.4946.1069.

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43

Matyushov, Dmitry V., and Gregory A. Voth. "Modeling the free energy surfaces of electron transfer in condensed phases." Journal of Chemical Physics 113, no. 13 (2000): 5413. http://dx.doi.org/10.1063/1.1289886.

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44

Murata, Shigeo, Maged El-Kemary, and M. Tachiya. "Two-Dimensional Free Energy Surfaces for Electron Transfer Reactions in Solution." International Journal of Photoenergy 2008 (2008): 1–8. http://dx.doi.org/10.1155/2008/150682.

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Change in intermolecular distance between electron donor (D) and acceptor (A) can induce intermolecular electron transfer (ET) even in nonpolar solvent, where solvent orientational polarization is absent. This was shown by making simple calculations of the energies of the initial and final states of ET. In the case of polar solvent, the free energies are functions of both D-A distance and solvent orientational polarization. On the basis of 2-dimensional free energy surfaces, the relation of Marcus ET and exciplex formation is discussed. The transient effect in fluorescence quenching was measured for several D-A pairs in a nonpolar solvent. The results were analyzed by assuming a distance dependence of the ET rate that is consistent with the above model.

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45

Agarwal, G. S., M. O. Scully, and H. Walther. "Atomic coherence initiated noise free energy transfer in a resonant medium." Optics Communications 106, no. 4-6 (March 1994): 237–41. http://dx.doi.org/10.1016/0030-4018(94)90329-8.

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46

Chu, Yuzhuo, Guohui Li, and Hong Guo. "QM/MM MD and free energy simulations of the methylation reactions catalyzed by protein arginine methyltransferase PRMT3." Canadian Journal of Chemistry 91, no. 7 (July 2013): 605–12. http://dx.doi.org/10.1139/cjc-2012-0483.

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Protein arginine N-methyltransferases (PRMTs) catalyze the transfer of methyl group(s) from S-adenosyl-l-methionine (AdoMet) to the guanidine group of arginine residue in abundant eukaryotic proteins. Two major types of PRMTs have been identified in mammalian cells. Type I PRMTs catalyze the formation of asymmetric ω-NG, NG-dimethylarginine (ADMA), while Type II PRMTs catalyze the formation of symmetric ω-NG, N′G-dimethylarginine (SDMA). The two different methylation products (ADMA or SDMA) of the substrate could lead to different biological consequences. Although PRMTs have been the subject of extensive experimental investigations, the origin of the product specificity remains unclear. In this study, quantum mechanical/molecular mechanical (QM/MM) molecular dynamics (MD) and free energy simulations are performed to study the reaction mechanism for one of Type I PRMTs, PRMT3, and to gain insights into the energetic origin of its product specificity (ADMA). Our simulations have identified some important interactions and proton transfers involving the active site residues. These interactions and proton transfers seem to be responsible, at least in part, in making the Nη2 atom of the substrate arginine the target of the both 1st and 2nd methylations, leading to the asymmetric dimethylation product. The simulations also suggest that the methyl transfer and proton transfer appear to be somehow concerted processes and that Glu326 is likely to function as the general base during the catalysis.

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47

CASCIOLA, C. M., and E. DE ANGELIS. "Energy transfer in turbulent polymer solutions." Journal of Fluid Mechanics 581 (May 22, 2007): 419–36. http://dx.doi.org/10.1017/s0022112007006003.

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The paper addresses a set of new equations concerning the scale-by-scale balance of turbulent fluctuations in dilute polymer solutions. The main difficulty is the energy associated with the polymers, which is not of a quadratic form in terms of the traditional descriptor of the micro-structure. A different choice is however possible, which, at least for mild stretching of the polymeric chains, directly leads to an L2 structure for the total free-energy density of the system thus allowing the extension of the classical method to polymeric fluids. On this basis, the energy budget in spectral space is discussed, providing the spectral decomposition of the energy of the system. New equations are also derived in physical space, to provide balance equations for the fluctuations in both the kinetic field and the micro-structure, thus extending, in a sense, the celebrated Kármán–Howarth and Kolmogorov equations of classical turbulence theory. The paper is limited to the context of homogeneous turbulence. However the necessary steps required to expand the treatment to wall-bounded flows of polymeric liquids are indicated in detail.

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48

Kapoor, Rajat, and S. T. Oyama. "Linear free energy relationships in solid state diffusion processes." Journal of Materials Research 12, no. 2 (February 1997): 474–79. http://dx.doi.org/10.1557/jmr.1997.0069.

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This paper presents a new form of linear free energy (LFE) relationship for diffusive mass transport in oxides and other binary compounds. The relationship applies to a family of related compounds. For a given substance, i, solid-state diffusivity is related to the equilibrium constant Ki or the free energy of transformation, , via a transfer coefficient γ, through the expression ln Di = γ ln Ki + constant . The system investigated here is the series of suboxide intermediates of vanadium pentoxide formed during temperature-programmed synthesis of vanadium nitride. The value of γ for this series is 0.27. The diffusivity values are determined by fitting a mathematical model to the experimental data. Diffusivity data are presented graphically in contour diagrams which correlate pre-exponential values, activation energies, particle sizes, and heating rates used in the temperature-programmed syntheses. An Evans–Polanyi linear relation, , relating activation energy, Ei, to enthalpy change of transformation, , via a transfer coefficient α = 0.53, is also shown to exist for the above system. The discrepancy between α and γ is resolved by using the Horiuti concept of the stoichiometric number of the rate-determining step.

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49

Guthrie, J. Peter. "Concerning the distant polar interaction in free energies of transfer. An explanation and an estimation procedure." Canadian Journal of Chemistry 69, no. 12 (December 1, 1991): 1893–903. http://dx.doi.org/10.1139/v91-274.

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For polyfunctional compounds, free energies of transfer from gas to aqueous solution require corrections for the interactions of polar groups (Distant Polar Interactions). These corrections can be made with very few adjustable parameters by using a model of the solvation process assuming hydrogen bonding is the major source of the effect on free energy of transfer for polar groups, and that hydrogen bonding is perturbed by polar effects, measured by Taft σ*. Parameters evaluated for polyfluoro, polychloro, and polybromo compounds successfully predicted the free energies of transfer for mixed polyhalogen compounds. Preliminary parameters have been evaluated for ethers, amines, phenyl groups, nitriles, and esters. Key words: free energy of transfer, distant polar interaction, hydrogen bonding, solvation.

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50

Senthilkumar, K., S. S. Naina Mohammed, and S. Kalaiselvan. "Free Radical Scavenging Activity of Dihydrocaffeic Acid: A Quantum Chemical Approach." Asian Journal of Chemistry 33, no. 4 (March 20, 2021): 937–44. http://dx.doi.org/10.14233/ajchem.2021.23068.

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Based on density functional theory (DFT), to investigate relationships between the antioxidant activity and structure of dihydrocaffeic acid, quantum chemical calculation is used. The optimized structures of the neutral, radical and ionic forms have been carried out by DFT-B3LYP method with the 6-311G(d,p) basis set. Reaction enthalpies related with the hydrogen atom transfer (HAT), single electron transfer proton transfer (SET-PT) and sequential proton loss and electron transfer (SPLET) were calculated in gas and water phase. The HOMO-LUMO energy gap, electron affinity, electronegativity, ionization energy, hardness, chemical potential, global softness and global electrophilicity were calculated by using the same level of theory. Surfaces with a molecular electrostatic potential (MEP) were studied to determine the reactive sites of dihydrocaffeic acid. The difference in energy between the donor and acceptor as well as the stabilization energy was determined through the natural bond orbital (NBO) analysis. The Fukui index (FI) based on electron density was employed to predict reaction sites. Reaction enthalpies are compared with previously published data for phenol and 3,4-dihydroxycinnamic acid.

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Journal articles on the topic 'Transfer free energy'

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