Hard hexagons: exact solution

  title={Hard hexagons: exact solution},
  author={Rodney J. Baxter},
  journal={Journal of Physics A},
  • R. Baxter
  • Published 1 March 1980
  • Mathematics
  • Journal of Physics A
The hard-hexagon model in lattice statistics (i.e. the triangular lattice gas with nearest-neighbour exclusion) has been solved exactly. It has a critical point when the activity z has the value 1/2(11+5 square root 5)=11.09017..., with exponents alpha =1/3, beta =1/9. More generally, a restricted class of square-lattice models with nearest-neighbour exclusion and non-zero diagonal interactions can be solved. 

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  • Physics
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  • 1978
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