Photoelectron spectroscopy of quinoline derivatives. Correlation of experimental ionization potentials with calculated molecular energies

Ahmed, Aftab; Julliard, Michel; Chanon, F.; Chanon, Michel; Gracian, F.; Pfister‐Guillouzo, G.

doi:10.1016/s1386-1425(96)01783-0

Cited by 9 publications

(4 citation statements)

References 20 publications

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“…The initial ionization energy of quinoline has been measured mainly by He I photoelectron spectroscopy. Reported values are 8.67 eV, 8.62 eV, ,− 8.65 eV, 8.61 ± 0.02 eV, as well as ion yield curve onset values of 8.62 ± 0.01 eV and 8.57 ± 0.05 eV . Reported successive ionization energies are 9.18, 9.39, 10.57, 11.3, 11.5, 11.9, and 12.4 eV. ,, We will refer to the ground doublet electronic state of quinoline as D 0 and to the successive excited states as D 1 –D 7 .…”

Section: Resultsmentioning

confidence: 99%

VUV Absorption Spectra of Gas-Phase Quinoline in the 3.5–10.7 eV Photon Energy Range

et al. 2018

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The absorption spectrum of quinoline was measured in the gas phase between 3.5 and 10.7 eV using a synchrotron photon source. A large number of sharp and broad spectral features were observed, some of which have plasmon-type collective π-electron modes contributing to their intensities. Eight valence electronic transitions were assigned, considerably extending the number of π-π* transitions previously observed mainly in solution. The principal factor in solution red-shifts is found to be the Lorentz-Lorenz polarizability parameter. Rydberg bands, observed for the first time, are analyzed into eight different series, converging to the D ground and two excited electronic states, namely, D and D, of the quinoline cation. The R1 series limit is 8.628 eV for the first ionization energy of quinoline, a value more precise than previously published. This value, combined with cation electronic transition data, provides precise energies, respectively, 10.623 and 11.355 eV, for the D and D states. The valence transition assignments are based on density functional theory (DFT) calculations as well as on earlier Pariser-Parr-Pople (P-P-P) self-consistent field linear combination of atomic orbitals molecular orbital results. The relative quality of the P-P-P and DFT data is discussed. Both are far from spectroscopic accuracy concerning electronic excited states but were nevertheless useful for our assignments. Our time-dependent DFT calculations of quinoline are excellent for its ground-state properties such as geometry, rotational constants, dipole moment, and vibrational frequencies, which agree well with experimental observations. Vibrational components of the valence and Rydberg transitions mainly involve C-H bend and C═C and C═N stretch modes. Astrophysical applications of the vacuum UV absorption of quinoline are briefly discussed.

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Section: Resultsmentioning

confidence: 99%

VUV Absorption Spectra of Gas-Phase Quinoline in the 3.5–10.7 eV Photon Energy Range

et al. 2018

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“…13,14 This method is state-of-the-art on ionization calculations and was utilized by Ahmed on the assignment of the photoelectron spectra of quinolines. 15 Tirapazamine (TPZ, 1) is the leading bioreductive agent currently undergoing advanced clinical trials for the penetration of radiotherapy and cisplatin chemotherapy. 16 TPZ is reduced by one-electron reductases to form a radical anion, and this oxygen-reversible process is the basis for its selective toxicity to hypoxic cells.…”

Section: Introductionmentioning

confidence: 99%

Theoretical Study of Adiabatic and Vertical Electron Affinity of Radiosensitizers in Solution Part 2: Analogues of Tirapazamine

Ramalho

Cunha

Alencastro

2004

J. Theor. Comput. Chem.

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Tirapazamine is a radiosensitizer, whose biological activity is associated to its electron affinity (EA). The electron affinity can be divided in two main processes: Vertical and Adiabatic. In this work, we calculated the EAs of nitroimidazoles ( Fig. 2) using HF and DFT methods and evaluated solvent effects (water and carbon tetrachloride) on EAs. For water, we combined the Polarized Continuum Model (PCM) and free energy perturbation (Finite Difference Thermodynamic Integration, FDTI) methods. For carbon tetrachloride, we used the FDTI method. The values of adiabatic EA obtained are in agreement with experimental data (deviations of 13.25 meV). The vertical EA were calculated according to Cederbaum's Outer Valence Green Function (OVGF) method. This study, which relays on theoretical aspects of free energy calculations on charged molecules in solution, could be helpful in the rational design of new and more selective bioreductive anticancer drugs.

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“…Chloroquinolines (3 − 5). The spectra of 3 − 5 (Figure ) can be assigned by comparison with the spectra of quinolin, chloropyridines, and 2-chloro-4-methylquinoline . The reference spectra serve to identify the position of chlorine lone pair bands.…”

Section: Resultsmentioning

confidence: 99%

“…The electronic structures of some quinolines, including the parent molecule, have been investigated previously by UV photoelectron spectroscopy (UPS) and semiempirical MO calculations. The compounds studied were quinoline, heptaquinoline, alkylquinolines and some isomeric methoxy, methyl, hydroxyl, and haloquinolines …”

Section: Introductionmentioning

confidence: 99%

UV Photoelectron Spectroscopic Study of Substituent Effects in Quinoline Derivatives

Novak

Kovač

2004

J. Org. Chem.

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The molecular and electronic structure of eight substituted quinolines has been investigated by HeI/HeII photoelectron spectroscopy, Green's function calculations, and comparison with the spectra of related compounds. The correlation between nitrogen lone pair ionization energies and basicity in 18 substituted quinolines is discussed. The influence of different substituents has been quantified via the scheme that is based on experimental energy shifts. The relationships between nitrogen ionization energies, pK(a) values, and medicinal activity are also discussed.

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Photoelectron spectroscopy of quinoline derivatives. Correlation of experimental ionization potentials with calculated molecular energies

Cited by 9 publications

References 20 publications

VUV Absorption Spectra of Gas-Phase Quinoline in the 3.5–10.7 eV Photon Energy Range

VUV Absorption Spectra of Gas-Phase Quinoline in the 3.5–10.7 eV Photon Energy Range

Theoretical Study of Adiabatic and Vertical Electron Affinity of Radiosensitizers in Solution Part 2: Analogues of Tirapazamine

UV Photoelectron Spectroscopic Study of Substituent Effects in Quinoline Derivatives

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