When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. DNA photoionization - Wikipedia

    en.wikipedia.org/wiki/DNA_photoionization

    Two properties are crucial regarding photoionization. On the one hand, the ionization energy (also called ionization potential, IP), refers to the energy necessary to remove one electron from a molecule; the lowest IP, corresponding to the ejection of a first electron, is the most biologically relevant factor. On the other hand, the ...

  3. Photoionization detector - Wikipedia

    en.wikipedia.org/wiki/Photoionization_detector

    In a photoionization detector, high-energy photons, typically in the vacuum ultraviolet (VUV) range, break molecules into positively charged ions. [2] As compounds enter the detector they are bombarded by high-energy UV photons and are ionized when they absorb the UV light, resulting in ejection of electrons and the formation of positively charged ions.

  4. Photoionization - Wikipedia

    en.wikipedia.org/wiki/Photoionization

    When either the laser intensity is further increased or a longer wavelength is applied as compared with the regime in which multi-photon ionization takes place, a quasi-stationary approach can be used and results in the distortion of the atomic potential in such a way that only a relatively low and narrow barrier between a bound state and the continuum states remains.

  5. Ion - Wikipedia

    en.wikipedia.org/wiki/Ion

    The energy required to detach an electron in its lowest energy state from an atom or molecule of a gas with less net electric charge is called the ionization potential, or ionization energy. The nth ionization energy of an atom is the energy required to detach its nth electron after the first n − 1 electrons have already been detached.

  6. Electron donor - Wikipedia

    en.wikipedia.org/wiki/Electron_donor

    The electron donating power of a donor molecule is measured by its ionization potential, which is the energy required to remove an electron from the highest occupied molecular orbital . The overall energy balance (ΔE), i.e., energy gained or lost, in an electron donor-acceptor transfer is determined by the difference between the acceptor's ...

  7. Appearance energy - Wikipedia

    en.wikipedia.org/wiki/Appearance_energy

    Appearance energy (also known as appearance potential) is the minimum energy that must be supplied to a gas phase atom or molecule in order to produce an ion. In mass spectrometry, it is accounted as the voltage to correspond for electron ionization. [1] This is the minimum electron energy that produces an ion. [2]

  8. Inductively coupled plasma mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Inductively_coupled_plasma...

    The high temperature of the plasma is sufficient to cause a very large portion of the sample to form ions. This fraction of ionization can approach 100% for some elements (e.g. sodium), but this is dependent on the ionization potential. A fraction of the formed ions passes through a ~1 mm hole (sampler cone) and then a ~0.4 mm hole (skimmer cone).

  9. Koopmans' theorem - Wikipedia

    en.wikipedia.org/wiki/Koopmans'_theorem

    For N 2 in contrast, the order of orbital energies is not identical to the order of ionization energies. Near-Hartree–Fock calculations with a large basis set indicate that the 1π u bonding orbital is the HOMO. However the lowest ionization energy corresponds to removal of an electron from the 3σ g bonding orbital. In this case the ...