Ground‐state structures of polymers

Two‐ and three‐dimensional structures A_xB_y can be characterized by the numbers T₁ and T₂ of nearest and next‐nearest neighbors of the same kind. A small number of structures at the border of the T₁, T₂ structure map is stabilized by enthalpy compared to an increased number of entropy stabilized structures. About 60 three‐dimensional structures with T₁=2 nearest neighbors of all A atoms are suitable for infinite chains of polymers like (CH)_∞, (CHCH₂)_∞, or (CH₂)_∞. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1944–1955, 2001