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Vertical Ionization Energies (vertical + ionization_energy)
Selected AbstractsTautomeric forms of adenine: Vertical ionization energies and Dyson orbitalsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 10 2010Raman K. Singh Abstract For the MP2/6-311++g(2df,p) optimized geometry of all the 14 adenine tautomers, the first three vertical ionization energies have been calculated using several electron propagator decouplings. The corresponding Dyson orbitals provide detailed insight into the role of structural variations in different adenine tautomers. Changes in the electron binding energies and the corresponding Dyson orbital amplitudes have been correlated with tautomeric proton shifts and changes in conjugation patterns. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 [source] A theoretical investigation of the excited states of OCLO radical, cation, and anion using the CASSCF/CASPT2 methodJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 2 2007Zi-Zhang Wei Abstract Using the complete active space self-consistent field method with a large atomic natural orbital basis set, 10, 13, and 9 electronic states of the OClO radical, OClO+ cation, and OClO, anion were calculated, respectively. Taking the further correlation effects into account, the second-order perturbation (CASPT2) calculations were carried out for the energetic calibration. The photoelectron spectroscopy of the OClO radical and OClO, anion were extensively studied in the both case of the adiabatic and vertical ionization energies. The calculated results presented the relatively complete assignment of the photoelectron bands of the experiments for OClO and its anion. Furthermore, the Rydberg states of the OClO radical were investigated by using multiconfigurational CASPT2 (MS-CASPT2) theory under the basis set of large atomic natural orbital functions augmented with an adapted 1s1p1d Rydberg functions that have specially been built for this study. Sixteen Rydberg states were obtained and the results were consistent with the experimental results. © 2006 Wiley Periodicals, Inc. J Comput Chem 28: 467,477, 2007 [source] Synthesis and Characteristics of a Nonaggregating Tris(tetrathiafulvaleno)dodecadehydro[18]annuleneCHEMISTRY - A EUROPEAN JOURNAL, Issue 33 2006Asbjørn Sune Andersson Abstract A new tris(tetrathiafulvaleno)dodecadehydro[18]annulene with six peripheral n -hexyl substituents was prepared by oxidative Glaser,Hay cyclization of a corresponding diethynylated tetrathiafulvalene (TTF) precursor. The electronic properties of the neutral and oxidized species were studied by both UV/Vis absorption spectroscopy and electrochemistry. From these studies, it transpires that the strongly violet-colored macrocycle does not aggregate in solution to any significant degree, which was confirmed by 1H NMR spectroscopy. This reluctance towards aggregation contrasts that observed for related TTF,annulenes containing other peripheral substitutents. Oxidation of the TTF,annulene occurs in two three-electron steps as inferred from both the peak amplitudes and the spectroelectrochemical study. We find that the tris(TTF)-fused dehydro[18]annulene is more difficult to oxidize (by +0.20 V) than the silyl-protected diethynylated mono-TTF precursor. In contrast, the first vertical ionization energy calculated at the B3,LYP/6,311+G(2d,p) level for the parent tris(TTF)-fused dehydro[18]annulene devoid of peripheral hexyl substituents is in fact lower (by 0.44 eV). Moreover, the surface morphology of 1,d drop-cast on a mica substrate was investigated by atomic force microscopy (AFM). Crystalline domains with slightly different orientations were observed. The thickness of individual layers seen in the crystalline domains and the thickness of a monolayer obtained from a very dilute solution were determined to 1.8,1.9 nm. This thickness corresponds to the diameter of the macrocycle and the layers seen in the film are apparently formed when the molecules stack in the horizontal direction relative to the substrate. [source] | ||||||||||