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Dispersion diagrams for the chiral triangular lattice, determined for (a,c,e,g) α = 0.8 and (b,d,f ,h) α = 1.2 and for decreasing values of ε: (a,b) ε = 0.1, (c,d) ε = 0.05, (e,f ) ε = 0.01, (g,h) ε = 0. The discrete triangular system exhibits six (three) dispersion surfaces for α < 1 (α > 1). A magnified inset of the neighbourhood of point K is included in (e) for later use (see §3c). (Online version in colour.)
