AC LEC 06-09

AC LEC 06-09 - Lecture 6 - Crystallography; Atomic...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Lecture 6 - Crystallography; Atomic Positions, Directions, Planes Atomic positions Directions Planes Miller Indices Vector Algebra dot products cross products Hexagonal Crystals Miller-Bravais Indices CLOSE PACKED DISPLAY OF ORANGES How to Get These Lectures? Oak/2008.01.SPR.ENG.MSE.150.02 MAT SCI 1 LECTURES Space Lattice and Crystal Structure Observations A space lattice is a geometrical array of points in space Each point has identical surroundings When the “lattice points” are populated by atoms, we get a “CRYSTAL STRUCTURE” Atomic Positions in Unit Cells Convention 1 Positive X: Direction coming out of sheet Positive Y: Direction going to right edge of sheet Positive Z: Direction going to top edge of sheet Atom positions are located using unit distances along x, y and z axes Lets stick with CUBIC Lattice for the moment: a = b = c +Y +X +Z-Z-Y-X (0,0,0) (0,0,-1) (0,1,0) (-1,0,0) (1,0,0) (0,-1,0) (0,0,1) BCC STRUCTURE +Y +X +Z (0,0,0) (0,1,0) (1,0,0) (0,0,1) (0,1,1) (1,1,0) (1,1,1) (1,0,1) (1/2,1/2,1/2) a a a BCC ROTATION MOVIE FCC STRUCTURE (0,1,0) (1,0,0) (0,0,1) +Y +X +Z (0,1,1) (1,1,0) (1,0,1) a a a (1,1/2,1/2) (1/2,1/2,0) (1/2,1,1/2) (0,1/2,1/2) (1/2,0,1/2) (1/2,1/2,1) (0,0,0) (1,1,1) FCC ROTATION MOVIE Directions in Crystals (1) Resolve the direction along the coordinate axes Reduce to integers Enclose in SQUARE BRACKETS (no commas) EXAMPLES OA [110] OE [111] OB [100] OH [1 ½ 0] [210] +Y + X +Z O A C B F G D E 1/2H Directions in Crystals (2)...
View Full Document

This note was uploaded on 02/27/2009 for the course MSE 150 taught by Professor Wittig during the Spring '07 term at Vanderbilt.

Page1 / 36

AC LEC 06-09 - Lecture 6 - Crystallography; Atomic...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online