(a) Ordered(b) DisorderedOrdering in metal alloys. Two different atom typesare interspersed: (a) ordered at low temperature, and(b) disordered at high temperature.Figure by MIT OCW.(a) Ordered(b) Disordered20001800160014001200100010008008006006004004002000 10 20 30 40 50 60 70 80 90 100Temperature (0C)Temperature (0F)Composition (wt% Zn)α + Lβ + Lη + Lηε + Lεδ + Lγ + Lα + βa + β'δ + εγ + εγε + ηδγ + δβ + γβ' + γβ'βThe copper-zinc phase diagram.Figure by MIT OCW.N1N1N2N2C2C2C2H7H3H1H2H3H1H7H2H5H4H4H6F21F21F21F21F22F22F1C3C1BC1C3baE0E1E2E3E4E511223 33 33334Projection of the low-temperature structure of (CH3)4NBF4 on the ab plane. In the high-temperaturephase, the orientations of the BF4 groups are randomly distributed among the four orientations obtainedby successive 900 rotations around the B-F axis perpendicular to the drawing.Figure by MIT OCW.262218140 150 160 170Experimental heat-capacity points from the stepmeasurements and from the thermograms in thetransition region.CP (R)T(K)Figure by MIT OCW.120804000 10 20 30 40 60 8004080120160ABC/J mol-1 K-1C/J mol-1 K-1The temperature dependence of the molar heat capacity fortwo individual DNP monomer single crystals. The full curveshows a Debye fit.Figure by MIT OCW.8060402000 0.2 0.4 0.6 0.8 1Spheres (BCC) Cylinders (HEX) Gyroid (GYR)BCC BCCLamellar (LAM)HEX HEXLAMGYRDisorderedDecreasing TemperatureχNfAFigure by MIT OCW.Images removed due to copyright reasons.EnergyMicrostate12345670nModel for a 3-atom solid as 1D harmonic oscillatorsDE = (9/2)hv - (7/2) hv = hvFigure by MIT
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