triplet
Quick Summary
In atomic physics, a triplet state refers to a condition where electrons in an atom or molecule have parallel spins, resulting in a net magnetic moment. This is in contrast to a singlet state, where electron spins are paired and cancel each other out.1
When an electron absorbs energy and moves to a higher energy level, it can either maintain its paired spin configuration (singlet state) or flip its spin to align parallel with its original partner (triplet state). Transitions between singlet and triplet states are typically forbidden by selection rules.1
Phosphorescence, a phenomenon where a molecule emits light after absorbing it, involves a transition from an excited singlet state to a triplet state, followed by a slow decay back to the singlet ground state. This process is related to the interactions between electron spins and their orbital motion.1
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photochemical reactionConsequences of photoexcitation…the molecule is in a triplet state. A change in intrinsic electron spin is not very probable, so conversion of a molecule from singlet to triplet or vice versa is slow compared with other molecular processes.
Read More…the molecule is in a triplet state. A change in intrinsic electron spin is not very probable, so conversion of a molecule from singlet to triplet or vice versa is slow compared with other molecular processes.
Read More- photochemical reactionConsequences of photoexcitation
(fluorescence), intersystem cross to a triplet state that rapidly internally converts to T1 (the lowest-energy triplet state), or undergo a chemical reaction. The T1 level can internally convert to S0, emit a photon (phosphorescence), or take part in a chemical reaction. This method of accessing the triplet states (intersystem crossing…
Read More(fluorescence), intersystem cross to a triplet state that rapidly internally converts to T1 (the lowest-energy triplet state), or undergo a chemical reaction. The T1 level can internally convert to S0, emit a photon (phosphorescence), or take part in a chemical reaction. This method of accessing the triplet states (intersystem crossing…
Read More - photochemical reactionConsequences of photoexcitation
Because the unpaired electrons of triplet states (with parallel spins) interact more strongly than those of singlet states (with opposing spins), the energy difference T1 − S0 is less than S1 − S0, and phosphorescence occurs at longer wavelengths than fluorescence. Also, the low probability of a spin change results…
Read MoreBecause the unpaired electrons of triplet states (with parallel spins) interact more strongly than those of singlet states (with opposing spins), the energy difference T1 − S0 is less than S1 − S0, and phosphorescence occurs at longer wavelengths than fluorescence. Also, the low probability of a spin change results…
Read More - photochemical reactionConsequences of photoexcitation
The excited singlet and triplet states may also absorb radiation and reach higher excited electronic levels. In general, this transient absorption spectrum is different from the absorption of the ground state, which allows monitoring of the time evolution of the excited states. This is accomplished by a sequence of…
Read MoreThe excited singlet and triplet states may also absorb radiation and reach higher excited electronic levels. In general, this transient absorption spectrum is different from the absorption of the ground state, which allows monitoring of the time evolution of the excited states. This is accomplished by a sequence of…
Read More - photochemical reactionPhotosensitization
…in that it is a triplet; hence, it can accept electronic energy from more-energetic triplet states of other molecules in a process called quenching (as in the case of the space shuttle wing described above). When this occurs, the donor molecule begins in its triplet state and undergoes a change…
Read More…in that it is a triplet; hence, it can accept electronic energy from more-energetic triplet states of other molecules in a process called quenching (as in the case of the space shuttle wing described above). When this occurs, the donor molecule begins in its triplet state and undergoes a change…
Read More - photochemical reactionPhotoprotection
…unavoidably generates large numbers of triplet states.
Read More…unavoidably generates large numbers of triplet states.
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