Atom vibrations

The atoms and ions of a crystalline lattice, which are bonded with each other with considerable inter molecular forces, are not motionless. Due to the consistent vibration induced from thermal energy, they are permanently deviating from their equilibrium position. Elastic waves of different lengths, frequencies, and amplitudes run through crystalline solids at all times. The frequencies are typically of the order of 1013 Hz, and the amplitudes are typically of the order of 10−11 m. The atoms and ions of a crystalline lattice, which are bonded with each other with considerable inter molecular forces, are not motionless. Due to the consistent vibration induced from thermal energy, they are permanently deviating from their equilibrium position. Elastic waves of different lengths, frequencies, and amplitudes run through crystalline solids at all times. The frequencies are typically of the order of 1013 Hz, and the amplitudes are typically of the order of 10−11 m. The process of the atomic vibrations is important for materials of different classes: for metallic, covalent, ionic crystals, semiconductors, intermetallic compounds, interstitial phases. The amplitude-frequency characteristics of the vibrating spectrum of an alloy can be varied, for example by alloying, to produce a well-directed effect on the properties of the materials.