Bonding electrons, ionization potential

In addition to the obvious structural information, vibrational spectra can also be obtained from both semi-empirical and ab initio calculations. Computer-generated IR and Raman spectra from ab initio calculations have already proved useful in the analysis of chloroaluminate ionic liquids [19]. Other useful information derived from quantum mechanical calculations include and chemical shifts, quadru-pole coupling constants, thermochemical properties, electron densities, bond energies, ionization potentials and electron affinities. As semiempirical and ab initio methods are improved over time, it is likely that investigators will come to consider theoretical calculations to be a routine procedure. 

It is surprisingly difficult to find reliable values of I and E a). Probably the most extensive collection of data is Bond Energies, Ionization Potentials and Electron Affinities by V. I. Vedeneyev, V. L. Gurvich, V. N. Kondrat yev, Y. A. Medvedev and Ye. L. Frankevich, Edward Arnold, London, 1966. The Chem Guide Website has several good pages, e.g. look at http //www.chemguide.co.uk/atoms/properties/eas.html. 

Fig. 7. Born-Haber cycle for the formation of ions by heterolytie fission of a covalent bond. I ionization potential of M, E electron affinity of X...

Ye. L. Bond energies, ionization potentials, and electron affinities. New York, N.Y. Scripta Technics Ltd., St. Martin s Press 1966. 

L.V. Gurvich, G.V. Karachevtsev, V.N. Kondratyev, Yu.A. Lebedev, V.A. Medvedev, V.K. Potapov and Yu.S. Khodeev, Energies of Chemical Bond Breaking. Ionization Potentials and Electron Affinity, Nauka, Moscow, 1974 (in Russian). 

The electronic properties of Ag cluster adsorbed on a C model have been examined by Baetzold (60). In this CNDO calculation, properties of interest included bond energies, ionization potential, and charge transfer with the substrate. A 10-atom C model consisting of fused hexagons was employed as the substrate. The 2 s and 2p orbitals of C are included in this calculation as well as the 4d, 5s, and 5p orbitals of Ag. 

The electron affinity of ClOt has been estimated from a Born—Haber cycle, employing a lattice energy calculation, to be 134 kcal mof (V. I. Medeoeyev, L. V. Gurvich, V. N. Kondrat yev, V. A. Medvedev, and Ye, L Frankevich, "Bond Energies, Ionization Potentials and Electron Affinities," St. Martin s Press, New York, N. Y., 1966), whereas the electron affinity of the P atom has been determined spectroscopically to be 79.5 d 0.1 kcal mol (R. S. Berry and C. W. Reimann, J. Ckem. Pkys., 18, 1540 (1963)). 

V. I. Vedeneyev, L. V. Gurvich, V. N. Kondratyev, V. A. Medvedev and Ye. L. Frankevich, Bond Energies, Ionization Potentials and Electron Affinities, Edward Arnold, London, 1966. 

Ye.L. Frankevich, "Bond Energies, Ionization Potentials and Electron Affinities", Edward Arnold, London, 1966, p.86. 

Vedeneyev, V. I., et al., Bond Energies, Ionization Potentials, and Electron Affinities, Arnold, 1965 (data tables). 

Determination of proton affinities (basicities) and acidities in the gas phase provides a means of systematically representing a large number of ion-molecule reactions and of the relationships between these quantities and bond strengths, ionization potentials and electron affinities without disturbance by solvation phenomena 47). 

Since the electron transfer structure D — A is of such importance in bonding donor and acceptor molecules, one might conclude that two of the most important factors influencing the strength of D A bonds are ionization potential of the donor molecule and electron affinity of the acceptor molecule. These quantities might also be considered as an absolute measure of donor and acceptor strength, in the sense that donor power is aided by low ionization potential and acceptor power by high electrpn affinity. 

Kondratiev, V. N. (Chief Editor), Bond Energy, Ionization Potential and Electron Affinity, [in Russian], Nauka Publishers Moscow, 1974, 83. 

We need only one valence orbital from each fluorine. We shall use in the discussion only the 2p orbital, since the molecular orbitals derived are appropriate for any combination of Is and Ip. However, it is probable that the very stable fluorine 2s orbital is not appreciably involved in the (s bonding. The ionization potential of an electron in the 2s orbital of fluorine is over 40 eV. 

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