triplet

spectroscopy

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July 14, 2026

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In spectroscopy, a triplet state refers to a molecular electronic configuration where two electrons have parallel spins, resulting in a net magnetic moment. This is in contrast to a singlet state, where electron spins are antiparallel and cancel each other out. Transitions between singlet and triplet states are typically forbidden by selection rules, meaning they are improbable. This phenomenon is closely related to phosphorescence, a type of luminescence where a substance emits light after excitation, with the emission persisting for a longer duration than in fluorescence due to the involvement of a metastable triplet state.12

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fine structure
… there are three components (triplets). This arises because the atoms of alkali metals have only one electron outside a closed core, or shell, of electrons, while the atoms of alkaline earths have two such electrons. Doublet separation for corresponding lines increases with atomic number; thus, with lithium (atomic number…
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… there are three components (triplets). This arises because the atoms of alkali metals have only one electron outside a closed core, or shell, of electrons, while the atoms of alkaline earths have two such electrons. Doublet separation for corresponding lines increases with atomic number; thus, with lithium (atomic number…
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chemical compound
Proton magnetic resonance spectroscopy
…three distinct peaks, called a triplet. The CH₂ peak is split into four peaks, called a quartet. These multiple peaks are caused by nearby hydrogen atoms through a process termed spin-spin splitting. Each set of equivalent hydrogens on a given carbon is split into an n+1 multiplet by adjacent hydrogen…
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…three distinct peaks, called a triplet. The CH₂ peak is split into four peaks, called a quartet. These multiple peaks are caused by nearby hydrogen atoms through a process termed spin-spin splitting. Each set of equivalent hydrogens on a given carbon is split into an n+1 multiplet by adjacent hydrogen…
Read More