radiationless

Subsequent to this, radiationless decay leads to a zwitterion ground state.

It is sometimes called "radiationless de-excitation", because no photons are emitted.

The lattice reduces the lifetime of the excited state by introducing radiationless decay mechanisms.

Intersystem crossing is a radiationless process involving a transition between two electronic states with different spin multiplicity.

A black dwarf emitted its last spray of infrared light and sank into the radiationless pit of dead stars.

As before, the presence of a fast, radiationless decay transition results in the population of the pump band being quickly depleted (N 0).

The process is a radiationless, almost resonant transfer of energy between sites and depends on the relative concentrations of the rare earth ions.

With the typical μM or less concentration of probe, the heat from radiationless decay is too small to affect the temperature of the solution.

Quenching refers to all radiationless deexcitation processes in which the excitation is degraded mainly to heat.

Quencher centres: where even the excited state of the centre is close to a radiationless transition level, so little or no luminescence is emitted.

Radiationless Processes, Eds.

He is known for the recognition and elucidation of the intramolecular nature of radiationless dissipation of energy in molecules of large and medium size.

These virtual photons are undetectable, since their existence violates the conservation of energy and momentum, and hence FRET is known as a radiationless mechanism.

Quantum electrodynamical calculations have been used to determine that radiationless (FRET) and radiative energy transfer are the short- and long-range asymptotes of a single unified mechanism.

It had already removed the radiationless lump of matter from the radiant mass that was Cliff Hawk, using the sleeth as its proxy; that had been disappointing, nothing had happened.

A general and quantitative discussion of intramolecular radiationless transitions is the subject of an article by M. Bixon and J. Jortner (J. Chem.

Beginning as early as 1933, George Adolphus Schott published a surprising discovery that a charged sphere in accelerated motion (such as the electron orbiting the nucleus) may have radiationless orbits.

This allows the possibility of a radiationless transition to the repulsive state whose energy levels form a continuum, so that there is blurring of the particular vibrational band in the vibrational progression.

It differs from intersystem crossing in that, while both are radiationless methods of de-excitation, the molecular spin state for internal conversion remains the same, whereas it changes for intersystem crossing.

Further investigation and theoretical work showed that the effect was a radiationless effect more than an internal conversion effect by use of elementary quantum mechanics and transition rate and transition probability calculations.

Observation of electron tracks independent of the frequency of the incident photon suggested a mechanism for electron ionization that was caused from an internal conversion of energy from a radiationless transition.

The large magnitude of vibronic coupling near avoided crossings and conical intersections allows wavefunctions to propagate from one adiabatic potential energy surface to another, giving rise to nonadiabatic phenomena such as radiationless decay.

However the El-Sayed's rule states that the rate of intersystem crossing, e.g. from the lowest singlet state to the triplet manifold, is relatively large if the radiationless transition involves a change of molecular orbital type.

This three phonon transition is mirrored in emission when the excited state quickly decays to its zero-point lattice vibration level by means of a radiationless process, and from there to the ground state via photon emission.

His contribution to the theoretical organic chemistry was based on Ab initio calculations of the radiationless transition of formaldehyde and ab initio calculations of single vibronic level fluorescence emission spectra and absolute radiative lifetimes of formaldehyde.