Atomic scale

Atomic spacing refers to the distance between the nuclei of atoms in a material. This space is extremely large compared to the size of the atomic nucleus, and is related to the chemical bonds which bind atoms together.

The spacing between atoms in most ordered solids is on the order of a few ångströms (a few tenths of a nanometer). In very low density gasses (for example, in outer space) the average distance between atoms can be as large as a meter.

The atomic spacing of crystalline structures is usually determined by passing an electromagnetic wave of known frequency through the material, and using the laws of diffraction to determine its atomic spacing.

Bond length can be determined between different elements in molecules by using the atomic radii of the atom. Carbon bonds with itself to form two covalent network solids.Diamond's C-C bond has a distance of 0.142 nm away from each carbon, while graphite's C-C bond has a distance of 0.341 nm away from each carbon. Although both bonds are between the same pair of elements they can still have different bond length.

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