CoreChem:Solids

From ChemPRIME

The most obvious distinguishing feature of a solid is its rigidity. On the microscopic level this corresponds to strong forces between the atoms, ions, or molecules relative to the degree of motion of those particles. The only movements within a solid crystal lattice are relatively restricted vibrations about an average position. Thus we often think and speak of crystalline solids as having atoms, ions, or molecules in fixed positions.