Vertical detachment energies

This agreement is unique to lowest-energy Sin it is absent even for other favorable isomers,22 e.g. those best for Sin or Sin+. This is clear simply from the inspection of vertical detachment energies (VDE)22 presented in Fig. 9 ... 

Figure 20-3. Electron binding energies for molecule M in anionic state are defined pictorially in a representation of the potential energy surfaces of the neutral molecule (M) and anion radical (M ) with the lowest vibration energy level shown for each. During a vertical process, the geometry remains unchanged but for the adiabatic process structural relaxation occurs. Thus the VDE (vertical detachment energy) and VEA (vertical electron affinity) represent the upper and lower bounds to the adiabatic electron affinity (AEA)...

The energy of stabilization of the anionic complex increases when acidity of alcohols increases (Figure 21-17). For anionic complexes for which we identified two minima corresponding to U HOR and UH OR structures, the structure with protonated uracil is more stable. The vertical detachment energy of anionic complex systematically increases when deprotonation energy of alcohol decreases. There is a discontinuity in VDE of ca. 0.5 eV, which is a manifestation of intermolecular proton transfer (Figure 21-18). 

Figure 21-18. The vertical detachment energy in anionic uracil-alcohol complexes versus the energy of deprotonation of the alcohol. All properties calculated at the B3LYP/6-31+- -G (5d) level of theory. PT and No PT are groups of complexes with and without proton transfer, respectively (Figure 5 of ref. [48]. Reprinted with permission. Copyright 2005 American Chemical Society.)...

In Figure 21-22 the optimized structures of neutral MAMT complexes are also displayed. The photoelectron spectra of (AT)- and (MAMT)- recorded with 2.54 eV photons are shown in Figure 21-23. The vertical detachment energies of these two spectra are very different, their values being separated by about 1 eV. The photoelectron spectrum of (AT)- consists of a broad peak with maximum at ca. 1.7 eV, while the photoelectron spectrum of (MAMT)- consists of a broad peak with a maximum at 0.7 eV (see Figure 21-23). 

Table 21-1. Values of stabilization energy (Estab), stabilization free energy (Gslab), their relative values (AE and AG calculated with respect to the Watson-Crickpair), electron vertical detachment energy (VDE) and adiabatic electron binding energy (EBE0) for the anionic adenine-thymine and 9-methyladenine-1-methylthymine complexes calculated at the B3LYP/6-31+G level. (Table 1 of ref. [49]. Reprinted with permission. Copyright 2005 American Chemical Society.)...

Table 21-2. Relative electronic energies and free energies (AE and AG) calculated with respect to the aHX(AT) or aHX(AT)-SPT anion together with the adiabatic electron affinities (AEAG) and electron vertical detachment energies (VDE) for the anionic HX(AT) complexes predicted at the B3LYP/6-31+G" level. AE and AG in kcal/mol AEAG and VDE in eV...

Table 5 Adiabatic detachment energies (ADE), vertical detachment energies (VDE), and reorganization energies of Fe+" complexes...

ADE = adiabatic detachment energies ESC A = electron spectroscopy for chemical analysis HOMO = highest occupied molecular orbitals MAES = metastable atom electron spectroscopy MIES = metastable ionization electron spectroscopy OAT = oxygen atom transfer PES = photoelectron spectra PEI = pulsed field ionization PIES = Penning ionization electron spectroscopy QM = quantum-mechanical REMPI = resonantly enhanced multiphoton ionization SC = semiclassical VDE = vertical detachment energies XPS = x-ray photoelectron spectroscopy ZEKE = zero electron kinetic energy Cp = cyclopentadienyl, Ph = phenyl, CeHs Tp =... 

Figure 5. Schematic energy diagram for photoexcitation into CTTS precursor states in I (water) clusters. Abs and VDE represent CTTS-type absorption and vertical detachment energy from the anion ground state, respectively.

VDEs, See Vertical detachment energies (VDEs) Vertical attachment energies (VAEs), 80 Vertical detachment energies (VDEs), 80 Vibrational spectroscopy, 66 Vicens and Westhof model system, 152 Voodoo graphics chip (1996), 5... 

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