A series of 18 alcohols (ROH) has been designed with an enthalpy of deprotonation in the gas phase (H(DP)) in the range 13.8-16.3 eV. The effects of excess electron attachment to the binary alcohol-uracil (ROH...U) complexes have been studied at the density functional level with a B3LYP exchange-correlation functional and at the second-order Møller-Plesset perturbation theory level. The photoelectron spectra of anionic complexes of uracil with 3 alcohols (ethanol, 2,2,3,3,3-pentafluoropropanol, and 1,1,1,3,3,3-hexafluoro-2-propanol) have been measured with 2.54 eV photons. For ROHs with deprotonation enthalpies larger than 14.8 eV, only the ROH...U- minimum exists on the potential energy surface of the anionic complex. For alcohols with deprotonation enthalpies in the range 14.3-14.8 eV, two minima might exist on the anionic potential energy surface, which correspond to the RO-...HU* and ROH...U- structures. For ROHs with deprotonation enthalpies smaller than 14.3 eV, the excess electron attachment to the ROH...U complex always induces a barrier-free proton transfer from the hydroxyl group of ROH to the O8 atom of U, with the product being RO-...HU*.
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http://dx.doi.org/10.1021/jp050246w | DOI Listing |
Dalton Trans
December 2024
Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, China.
The extraction and complexation of trivalent americium (Am) and lanthanides (Ln) using an asymmetric picolinic acid-derived tridentate N,O-hybrid ligand, 6-(dioctylcarbamoyl)picolinic acid (DOAPA), have been studied through both experimental and theoretical methods. DOAPA exhibits effective and fast extraction of Am(III) and Ln(III). The extraction is driven by favorable enthalpy change.
View Article and Find Full Text PDFCurr Opin Chem Biol
December 2024
Université libre de Bruxelles (ULB), Engineering of Molecular NanoSystems, Ecole Polytechnique de Bruxelles, Avenue F. Roosevelt 50, CP165/64, B-1050 Brussels, Belgium. Electronic address:
This brief review highlights recent advances in the transport of oxoanions using synthetic carriers, focusing on both progress and ongoing challenges in the field. The difficulty of transporting these oxoanions increases with their hydration enthalpies, with less hydrated nitrate and perchlorate being relatively easy to transport. Recent progress has focused on the transport of moderately hydrated anions such as bicarbonate and carboxylates, where studies are influenced by the free diffusion of neutral species obtained by (de)protonation equilibria.
View Article and Find Full Text PDFJ Phys Chem A
September 2024
Center for Computational Sciences, University of Tsukuba, Tsukuba 305-8577, Japan.
The design and synthesis of neutral organic superacids have been of interest recently due to their vast applications in chemistry and material sciences, for example, olefinic polymerization, isolation of highly reactive short-lived cations, etc. Cyclopentadiene behaves as a mild organic acid, producing a stable conjugate base by gaining aromaticity and conjugation after deprotonation. To stabilize conjugate bases of organic acids to show superacidities and hyperacidities, we considered aromatic phenyl substituents with cyclopentadiene (mono-, di-, and triphenyl-substituted cyclopentadiene and their cyano derivatives).
View Article and Find Full Text PDFInt J Mol Sci
June 2024
Department of Physics, Ivanovo State University of Chemistry and Technology, Sheremetevskiy Avenue 7, 153000 Ivanovo, Russia.
Using quantum chemical calculation data obtained by the DFT method with the B3PW91/TZVP and M062X/def2TZVP theory levels, the possibility of the existence of four Be(II) coordination compounds, each of which contains in the inner coordination sphere and the double deprotonated forms of subporphyrazine (H), mono[benzo]subporphyrazine (H), di[benzo]subporphyrazine (H), and tri[benzo]subporphyrazine (subphthalocyanine) (H) with a ratio Be(II) ion/ligand = 1:1, were examined Selected geometric parameters of the molecular structures of these (666)macrotricyclic complexes with closed contours are given; it was noted that BeN3 chelate nodes have a trigonal-pyramidal structure and exhibit a very significant (almost 30°) deviation from coplanarity; however, all three 6-membered metal-chelate and three 5-membered non-chelate rings in each of these compounds are practically planar and deviate from coplanarity by no more than 2.5°. The bond angles between two nitrogen atoms and a Be atom are equal to 60° (in the [Be] and [Be]) or less by no more than 0.
View Article and Find Full Text PDFAdv Mater
July 2024
Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, P. R. China.
Mott-Schottky construction and plasmon excitation represent two highly-efficient and closely-linked coping strategies to the high energy loss of oxygen evolution reaction (OER), but the combined effect has rarely been investigated. Herein, with Ag nanoparticles as electronic structure regulator and plasmon exciter, Ag/CoV-LDH@G nanohybrids (NHs) with Mott-Schottky heterojunction and notable plasmon effect are well-designed. Combining theoretical calculations with experiments, it is found that the Mott-Schottky construction modulates the Fermi level/energy band structure of CoV-LDH, which in turn leads to lowered d-band center (from -0.
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