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If the liquid is cooled slowly, thermal mobility is lost. The atoms areoften able to line themselves up and form a pure crystal that is completely orderedover a distance up to billions of times the size of an individual atom in all directions.This crystal is the state of minimum energy for this system. The amazing fact is that,for slowly cooled systems, nature is able to find this minimum energy state. In fact, ifa liquid metal is cooled quickly or “quenched,” it does not reach this state but ratherends up in a polycrystalline or amorphous state having somewhat higher energy.So the essence of the process is slow cooling, allowing ample time forredistribution of the atoms as they lose mobility. This is the technical definition ofannealing, and it is essential for ensuring that a low energy state will be achieved.Sample page from NUMERICAL RECIPES IN C: THE ART OF SCIENTIFIC COMPUTING (ISBN 0-521-43108-5)Copyright (C) 1988-1992 by Cambridge University Press.Programs Copyright (C) 1988-1992 by Numerical Recipes Software.Permission is granted for internet users to make one paper copy for their own personal use.
Further reproduction, or any copying of machinereadable files (including this one) to any servercomputer, is strictly prohibited. To order Numerical Recipes books,diskettes, or CDROMsvisit website http://www.nr.com or call 1-800-872-7423 (North America only),or send email to trade@cup.cam.ac.uk (outside North America).10.9 Simulated Annealing Methods.