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Carbon Allotropes, Band Theory of Solids

  • Network solids are giant molecules

  • Difference between graphite – sheets of hexagons of C – and diamond – 3D tetrahedral network; properties related to structures

  • Novel carbon frameworks C-60 – buckyball; nanotubes

  • Conductivity varies metals >> semiconductors > insulators

  • In large crystals MOs combine to give bands; valence band; conduction band

  • Doping of insulator like Si with P gives n-type semiconductor

  • Doping of Si with Al gives p-type semiconductor

  • p/n junctions yield transistors and chips

  • Glasses: common ones made from quartz, sodium carbonate, calcium oxide; amorphous

Carbon Allotropes, Band Theory of Solids

Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.

Advanced Placement Chemistry