Abstract In this work, we distinguish the isospin for the first time and study the diquark–diquark–antiquark type udscc u d s c c ¯ pentaquark states with zero isospin via the QCD sum rules systematically. We distinguish contributions of the pentaquark states with negative parity from positive parity unambiguously and obtain clean QCD sum rules for the pentaquark states with negative parity. Then we adopt the modified energy scale formula to choose the optimal energy scales of the QCD spectral densities, and obtain the mass spectrum of the udscc u d s c c ¯ pentaquark states with the quantum numbers I=0 I = 0 and J^P=1{2}^- J P = 1 2 -, 3{2}^- 3 2 -, 5{2}^- 5 2 -, which could interpret the P₂ₒ (4338) P cs (4338) and P₂ₒ (4459) P cs (4459) in the J/ J / ψ Λ mass spectrum naturally.
Wang et al. (Tue,) studied this question.