Three‐quark nucleon interpolating fields in QCD have well‐defined SUL(3)×SUR(3) and UA(1) chiral transformation properties, viz. [(6,3)⊕(3,6)], [(3,3̄)⊕(3̄,3)], [(8,1)⊕(1,8)] and their “mirror” images, Ref. [1]. It has been shown (phenomenologically) in Ref. [2] that mixing of the [(6,3)⊕(3,6)] chiral multiplet with one ordinary (“naive”) and one “mirror” field belonging to the [(3,3̄) ⊕ (3̄,3)], [(8,1) ⊕ (1,8)] multiplets can be used to fit the values of the isovector (gA(3)) and the flavor‐singlet (isoscalar) axial coupling (gA(0)) of the nucleon and then predict the axial F and D coefficients, or vice versa, in reasonable agreement with experiment. In an attempt to derive such mixing from an effective Lagrangian, we construct all SUL(3)×SUR(3) chirally invariant non‐derivative one‐meson‐baryon interactions and then calculate the mixing angles in terms of baryons’ masses. It turns out that there are (strong) selection rules: for example, there is only one non‐derivative chirally symmetric interaction between J = 1/2 fields belonging to the [(6,3) ⊕ (3,6)] and the [(3,3̄) ⊕ (3̄,3)] chiral multiplets, that is also UA(1) symmetric. We also study the chiral interactions of the [(3,3̄) ⊕ (3̄,3)] and [(8,1)⊕ ( 1,8)] nucleon fields. Again, there are selection rules that allow only one off‐diagonal non‐derivative chiral SUL(3)×SUR(3) interaction of this type, that also explicitly breaks the UA(1) symmetry. We use this interaction to calculate the corresponding mixing angles in terms of baryon masses and fit two lowest lying observed nucleon (resonance) masses, thus predicting the third (J = 1/2, I = 3/2) Δ resonance, as well as one or two flavor‐singlet Λ hyperon(s), depending on the type of mixing. The effective chiral Lagrangians derived here may be applied to high density matter calculations.

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