Ground‐state structures of polymers

Two‐ and three‐dimensional structures A x B y can be characterized by the numbers T 1 and T 2 of nearest and next‐nearest neighbors of the same kind. A small number of structures at the border of the T 1 , T 2 structure map is stabilized by enthalpy compared to an increased number of entropy stabilized structures. About 60 three‐dimensional structures with T 1 =2 nearest neighbors of all A atoms are suitable for infinite chains of polymers like (CH) ∞ , (CHCH 2 ) ∞ , or (CH 2 ) ∞ . © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1944–1955, 2001