|MadSci Network: Physics|
Richard, I am not certain what you are calling a crystaline net. Material science people often refer to a crystalline lattice. Most metals consist of multiple crystals which together form a crystalline lattice. The area between the crystals often contains impurities like sulphur or phosphorus. Metals can be grown as very large single crystals. The single crystal still has electrical resistance at ambient (room) temperatures. The impurities at the grain boundaries will contribute to increased resistance compared to a single crystal. Only when a conductor is cooled below it's superconducting transition temperature does the electrical resistance become zero. Bob Novak Specialist - Process R&D Carpenter Technology
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