Topology on representative angular planes for symmetric ACR S₆ located at (e₁e₂,e₃) = (0.0569, 0.0846, 0.0531). (a) Topology on (θ₁₂, Δϖ₁₂) plane with fixed (θ₂₃, Δϖ₂₃) = (0, π). The saddle-like point at (θ₁₂, Δϖ₁₂) = (0, π) marked by a cross indicates the instability of this solution, while two asymmetric ACRs bifurcated from this unstable symmetric one are indicated by black dots. (b) The topology on (θ₂₃, Δϖ₂₃) plane with (θ₁₂, Δϖ₁₂) fixed to (0, π). The node-like point at (θ₂₃, Δϖ₂₃) = (0, π) is marked by a pink dot.