atomic displacements

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• Molecular Hamiltonian — In atomic, molecular, and optical physics as well as in quantum chemistry, molecular Hamiltonian is the name given to the Hamiltonian representing the energy of the electrons and nuclei in a molecule. This Hermitian operator and the associated… …   Wikipedia

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• Topotactic — In chemistry, a topotactic transformation is characterised by internal atomic displacements, which may include loss or gain of material, so that the initial and final lattices are in coherence. An example would be the oxidation of magnetite to… …   Wikipedia

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• solids, mechanics of — ▪ physics Introduction       science concerned with the stressing (stress), deformation (deformation and flow), and failure of solid materials and structures.       What, then, is a solid? Any material, fluid or solid, can support normal forces.… …   Universalium

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• Threshold displacement energy — The threshold displacement energy Td is the minimum kinetic energy that an atom in a solid needs to be permanently displaced from its lattice site to a defect position. It is also known as displacement threshold energy or just displacement energy …   Wikipedia

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