RHF Ab initio electronic and molecular structures of a ((SINGLEBOND)Be2(SINGLEBOND))∞ chain

Ab initio RHF/STO-3G, 3-21~, and 6-31~ band structure calculations were carried out on an extended regular chain of beryllium atoms (--Bez-)= to study its stability in comparison with corresponding data on finite chains and previously reported results on small elemental beryllium clusters. It is found that, starting from a linear distribution of atoms along the chain, the system evolves toward a regular zigzag planar structure. The total RHF energy per constituent atom is higher for the chains than for the clusters and is thereby suggestive of that isolated chains are unlikely to exist except in constraining channels of host structures. In the limit of the infinite chain, there are signs indicating that the RHF model is no longer an adequate description. 0 1996 John Wiley & Sons, Inc.