Nichtstöchiometrischen
Nichtstöchiometrischen refers to compounds where the ratio of elements does not conform to the simple whole-number ratios typically found in stoichiometric compounds. These substances are also known as berthollides. The deviation from ideal stoichiometry arises from defects in the crystal lattice structure. Common defects include vacancies, where an atom is missing from its expected position, or interstitial atoms, where an atom occupies a site not normally part of the lattice. These imperfections lead to a non-integer ratio of elements. For example, some metal oxides and sulfides exhibit non-stoichiometry, such as iron(II,III) oxide (Fe3O4), which can exist with a slight excess or deficit of oxygen. Non-stoichiometric compounds are important in various fields, including catalysis, solid-state chemistry, and materials science, as their properties can be significantly influenced by the presence and type of defects. Understanding these deviations is crucial for controlling and predicting the behavior of these materials.