triplet state

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trip·let state

a second excited state of a molecule (for example, chlorophyll) produced by absorption of light to produce the singlet state, then loss of some energy (fluorescence) to achieve the longer-lasting triplet state The molecule may remain sufficiently long in the triplet state for a second activating light quantum to be effective in producing a "second triplet" state, at a still-higher level of excitation, hence reactivity. Alternatively, the molecule may lose the triplet state energy directly and return to the ground state.
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0)] Initiator diradical without undecomposed peroxide groups generated by total decomposition.
2)] Monomer diradical with two undecomposed peroxide groups.
0)] Monomer diradical without undecomposed peroxide groups.
i)] PS diradical of chain length n containing i undecomposed peroxide groups.
n] Stoichiometric coefficient corresponding to a PS diradical of chain length n generated by total decomposition of a polymer with undecomposed peroxide groups.
Note the following: (i) when two monoradicals with i and j undecomposed peroxide groups terminate, the formed polymer will contain i+j undecomposed peroxide groups; (ii) diradicals only have an even number of peroxide groups, as they are generated only by propagation of the initiator diradical (with only two peroxide groups), and by combination termination of other diradicals, all of which have an even number of peroxide groups or no peroxide groups; (iii) due to assumption (c), polymeric chains may suffer both sequential decomposition reactions or total decompositions reactions.
Polymers with two undecomposed peroxide groups have higher concentration than polymers with a higher number of undecomposed peroxide groups, because these are the main products of an initiator diradical (1) that propagated and terminated to form a polymeric chain.
The Basic Module of Appendix A allows the prediction of global chemical species' evolution along the reaction (total mono- and diradicals, total polymer).
One of the tactics is to produce a diradical molecule that will be used for complexion with metal ions to form molecular magnets.
This zig-zag arrangement of stacked plates is also found for the 1,3-phenylene bridged diradicals |C.
Bob Crawford, FCIC, was a pioneer in the study of diradicals derived from thermolysis and photolysis of cyclic azo compounds.
In addition, the group is attempting to evaluate the importance of substituent effects on the reactivity and stability of free radicals, diradicals and triplets.