Should recombinations of radical pairs be considered as accompanied by measurements?

The so-called phenomenological kinetic equation for one-pair density operator for spin-selective reactions is defended. We derive this equation from the kinetic equation for density operator of all pairs which are treated as singlet and triplet bosons. There presented some reasons for inconsistency of measurement-like approach to the problem.

Spin multiplicity and entanglement swapping in radical ion recombinations

We address the problem of relative frequencies of singlet and triplet recombinations in a multiparticle system, which consists of spin-correlated radical ion pairs. The nonlocal swapping of spin correlations due to cross-recombinations is taken into account. It is shown that this swapping does not contribute to singlet and triplet recombination frequencies in the absence of spin evolution in the correlated pairs.