Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Reaction operators for spin-selective chemical reactions of radical
  pairs   Spin-selective reactions of radical pairs have traditionally been modelled
theoretically by adding phenomenological rate equations to the quantum
mechanical equation of motion of the radical pair spin density matrix. More
recently an alternative set of rate expressions, based on a quantum measurement
approach, has been suggested. Here we show how these two reaction operators can
be seen as limiting cases of a more general reaction scheme.

17
The categories of this paper are: q-fin
2
The categories of this paper are: math
25
The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
23
The categories of this paper are: solv-int
24
The categories of this paper are: dg-ga
14
The categories of this paper are: math-ph
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th