Abstract
The interplay of atomic geometry and electronic structure is studied by means of ab initio total-energy and electronic-structure calculations for quasi-one-dimensional systems with different translational symmetries , , and . The chain structure and the trimer formation are related to the details of the electronic band structure. Despite the opening of band gaps during reconstruction, no true metal-insulator transition is observed. We show that the phase transitions do not give rise to well-pronounced charge-density waves in electron density. We demonstrate that a certain chainlike scanning tunneling microscopy image for a given bias voltage does not allow direct conclusions concerning the formation of a one-dimensional charge-density wave. The electron redistributions are identified to play an important role for the transition . Only a weak tendency for spin ordering accompanying the surface reconstruction is found within the used spin-polarized density functional calculations.
1 More- Received 13 April 2005
DOI:https://doi.org/10.1103/PhysRevB.73.035430
©2006 American Physical Society