Abstract
The relaxations and vibrational properties of dihydride steps on the Si(111):H surface are studied from first principles. Besides the expected large relaxation of the unit on the step edge, long-range relaxations are found along a zigzag chain deep into the bulk. Three vibrational modes are found with frequencies 10.9, 22.5, and 56.0 higher than the Si-H stretching frequency on the terrace. A scissors mode is identified with frequency 262 higher than the Si-H wagging frequency. These frequency differences and mode assignments are in good agreement with experiment.
- Received 18 February 1994
DOI:https://doi.org/10.1103/PhysRevB.50.4637
©1994 American Physical Society