SURFACE MAGNETISM OF SILICON [111](7×7) AND [001](2×1) SURFACES: QUANTUM-CHEMICAL APPROACH Article Sheka E.F., Nikitina E.A., Aono M. 1999 9th International Crimean Microwave Conference: Microwave and Telecommunication Technology, CriMiCo 1999 - Conference Proceedings. Institute of Electrical and Electronics Engineers Inc.. 1999.