MATS 3011 Lecture Notes - Paper Size, Moodle, Interstitial Defect
Document Summary
Exam 1 next week wedfeb 19 during class. Half page cheat sheet allowed (hand-written, one side) Intensity: tabulate sin2(theta) for each observed peaks, calculate sin2(theta)/sin2(theta from first peak, look for pattern in #2. If the values in #2 is equispaced & 7 missing --> sc. If the values in #2 are 1, 1. 33, 2. 66, --> fcc. Theta sin2(theta) sin2(theta)/sin2(theta_first peak) (110) (200) (211) (220) (310) (222) (321) *on an exam, check the 2 and 7, if not there, it"s fcc. -> 2dsin(theta) = n say, n = 1. ->2(a/sqrt[h2 + k2 + l2])sin(20) = 1. 542 a = (1. 542*sqrt[h2 + k2 + l2])/(2sin(20)) a = 2. 25sqrt[h2 + k2 + l2] ao. For bcc, get first peak at 110not 001 a = 2. 25sqrt[12 + 12 + 02] ao a = 3. 18 ao. R = sqrt[3]a/4 = 0. 137 nm ---> from textbook, can tell that it is tungsten. Defects are not always bad; if they"re controlled, that"s good.
