Surface electronic structure calculations using the MBJLDA potential: application to Si(111)2 × 1

The Si(111)2 × 1 surface has been widely studied via a range of different experimental and theoretical techniques, and found to adopt a π-bonded chain configuration. To determine an accurate electronic structure for this system, however, it has been found necessary to use sophisticated and very computationally expensive methods such as GW or hybrid functionals. In this article, we show that the MBJLDA approach, originally proposed by Tran and Blaha for bulk materials (Tran and Blaha, Phys. Rev. Lett. 2009, 102, 226401), yields results which are comparable to GW, and generally superior to those obtained from hybrid functional density functional theory calculations. The MBJLDA method is also substantially more computationally efficient. A procedure and justification for the application of the MBJLDA approach to surfaces in general is also provided.