Results of a correlation calculation for the ground state of polyethylene, as obtained within the local ansatz, are presented. The starting point is a SCF ground state calculated within a doublehyphen;zeta basis. For the correlation part, the basis is extended by including a set of polarization functions on each atom. The correlation computations are inexpensive and fast converging. On correcting for finite basis set deficiencies, an estimate of the binding energy is obtained which is very close to experiment. Pair correlation functions are also discussed. These compare well to those obtained previously for small hydrocarbon molecules and diamond, where similar bond patterns occur. The computation scheme itself contains a new feature, which allows for an improved use of the translational symmetry.
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